samples: openthread: Drop support for L2 in coprocessor

L2 variant is not needed in coprocessor sample. We can use there
only the raw nrf-radio version.

Signed-off-by: Arkadiusz Balys <[email protected]>

Author: ArekBalysNordic

samples/openthread/coprocessor/README.rst

@@ -121,8 +121,6 @@ The following snippets are available:
      The ``usb`` snippet does not support the ``nrf54l15dk/nrf54l15/cpuapp``, ``nrf54l15dk/nrf54l10/cpuapp`` and ``nrf54l15dk/nrf54l05/cpuapp`` board targets.
 
 * ``hci`` - Enables support for the Bluetooth HCI interface parallel to :ref:`Thread RCP <thread_architectures_designs_cp_rcp>`.
-* ``l2`` - Enables the Zephyr networking layer.
-* ``logging_l2`` - Enables logging from the Zephyr networking layer.
 
 FEM support
 ===========

samples/openthread/coprocessor/sample.yaml

@@ -88,24 +88,3 @@ tests:
       - nrf21540dk/nrf52840
     integration_platforms:
       - nrf52840dk/nrf52840
-  sample.openthread.coprocessor.l2:
-    sysbuild: true
-    build_only: true
-    tags:
-      - ci_build
-      - sysbuild
-      - ci_samples_openthread
-    platform_allow:
-      - nrf52840dk/nrf52840
-      - nrf54l15dk/nrf54l15/cpuapp
-      - nrf54l15dk/nrf54l10/cpuapp
-      - nrf54lm20dk/nrf54lm20a/cpuapp
-      - nrf54l15dk/nrf54l15/cpuapp/ns
-    extra_args:
-      - coprocessor_SNIPPET="ci;l2"
-    integration_platforms:
-      - nrf52840dk/nrf52840
-      - nrf54l15dk/nrf54l15/cpuapp
-      - nrf54l15dk/nrf54l10/cpuapp
-      - nrf54lm20dk/nrf54lm20a/cpuapp
-      - nrf54l15dk/nrf54l15/cpuapp/ns