doc: Add 2.6.4 release to main

Add 2.6.4 release to main

Signed-off-by: Richa Pandey <[email protected]>

Author: richabp

doc/nrf/links.txt

@@ -451,6 +451,7 @@
 .. _`known issues for nRF Connect SDK v2.9.0`: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/releases_and_maturity/known_issues.html?v=v2-9-0
 .. _`known issues for nRF Connect SDK v2.8.0`: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/releases_and_maturity/known_issues.html?v=v2-8-0
 .. _`known issues for nRF Connect SDK v2.7.0`: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/releases_and_maturity/known_issues.html?v=v2-7-0
+.. _`known issues for nRF Connect SDK v2.6.4`: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/releases_and_maturity/known_issues.html?v=v2-6-4
 .. _`known issues for nRF Connect SDK v2.6.3`: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/releases_and_maturity/known_issues.html?v=v2-6-3
 .. _`known issues for nRF Connect SDK v2.6.2`: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/releases_and_maturity/known_issues.html?v=v2-6-2
 .. _`known issues for nRF Connect SDK v2.6.1`: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/releases_and_maturity/known_issues.html?v=v2-6-1
@@ -513,6 +514,7 @@
 .. _`Repositories and revisions for v2.7.99-cs2`: https://docs.nordicsemi.com/bundle/ncs-2.7.99-cs2/page/nrf/releases_and_maturity/repository_revisions.html
 .. _`Repositories and revisions for v2.7.99-cs1`: https://docs.nordicsemi.com/bundle/ncs-2.7.99-cs1/page/nrf/releases_and_maturity/repository_revisions.html
 .. _`Repositories and revisions for v2.7.0`: https://docs.nordicsemi.com/bundle/ncs-2.7.0/page/nrf/releases_and_maturity/repository_revisions.html
+.. _`Repositories and revisions for v2.6.4`: https://docs.nordicsemi.com/bundle/ncs-2.6.4/page/nrf/releases_and_maturity/repository_revisions.html
 .. _`Repositories and revisions for v2.6.3`: https://docs.nordicsemi.com/bundle/ncs-2.6.3/page/nrf/releases_and_maturity/repository_revisions.html
 .. _`Repositories and revisions for v2.6.2`: https://docs.nordicsemi.com/bundle/ncs-2.6.2/page/nrf/releases_and_maturity/repository_revisions.html
 .. _`Repositories and revisions for v2.6.99-cs1`: https://docs.nordicsemi.com/bundle/ncs-2.6.99-cs1/page/nrf/releases_and_maturity/repository_revisions.html
@@ -545,6 +547,7 @@
 .. _`Modem library changelog for v2.9.0`: https://docs.nordicsemi.com/bundle/ncs-2.9.0/page/nrfxlib/nrf_modem/doc/CHANGELOG.html#nrf-modem-changelog
 .. _`Modem library changelog for v2.8.0`: https://docs.nordicsemi.com/bundle/ncs-2.8.0/page/nrfxlib/nrf_modem/doc/CHANGELOG.html#nrf-modem-changelog
 .. _`Modem library changelog for v2.7.0`: https://docs.nordicsemi.com/bundle/ncs-2.7.0/page/nrfxlib/nrf_modem/doc/CHANGELOG.html#nrf-modem-changelog
+.. _`Modem library changelog for v2.6.4`: https://docs.nordicsemi.com/bundle/ncs-2.6.4/page/nrfxlib/nrf_modem/doc/CHANGELOG.html#nrf-modem-changelog
 .. _`Modem library changelog for v2.6.3`: https://docs.nordicsemi.com/bundle/ncs-2.6.3/page/nrfxlib/nrf_modem/doc/CHANGELOG.html#nrf-modem-changelog
 .. _`Modem library changelog for v2.6.2`: https://docs.nordicsemi.com/bundle/ncs-2.6.2/page/nrfxlib/nrf_modem/doc/CHANGELOG.html#nrf-modem-changelog
 .. _`Modem library changelog for v2.6.1`: https://docs.nordicsemi.com/bundle/ncs-2.6.1/page/nrfxlib/nrf_modem/doc/CHANGELOG.html#nrf-modem-changelog
@@ -576,6 +579,7 @@
 .. _`LwM2M carrier library changelog for v2.9.0`: https://docs.nordicsemi.com/bundle/ncs-2.9.0/page/nrf/libraries/bin/lwm2m_carrier/CHANGELOG.html#liblwm2m-carrier-changelog
 .. _`LwM2M carrier library changelog for v2.8.0`: https://docs.nordicsemi.com/bundle/ncs-2.8.0/page/nrf/libraries/bin/lwm2m_carrier/CHANGELOG.html#liblwm2m-carrier-changelog
 .. _`LwM2M carrier library changelog for v2.7.0`: https://docs.nordicsemi.com/bundle/ncs-2.7.0/page/nrf/libraries/bin/lwm2m_carrier/CHANGELOG.html#liblwm2m-carrier-changelog
+.. _`LwM2M carrier library changelog for v2.6.4`: https://docs.nordicsemi.com/bundle/ncs-2.6.4/page/nrf/libraries/bin/lwm2m_carrier/CHANGELOG.html#liblwm2m-carrier-changelog
 .. _`LwM2M carrier library changelog for v2.6.3`: https://docs.nordicsemi.com/bundle/ncs-2.6.3/page/nrf/libraries/bin/lwm2m_carrier/CHANGELOG.html#liblwm2m-carrier-changelog
 .. _`LwM2M carrier library changelog for v2.6.2`: https://docs.nordicsemi.com/bundle/ncs-2.6.2/page/nrf/libraries/bin/lwm2m_carrier/CHANGELOG.html#liblwm2m-carrier-changelog
 .. _`LwM2M carrier library changelog for v2.6.1`: https://docs.nordicsemi.com/bundle/ncs-2.6.1/page/nrf/libraries/bin/lwm2m_carrier/CHANGELOG.html#liblwm2m-carrier-changelog