doc: nrf: drop warnings_filter extension

It's no longer required as we're not using breathe anymore.

Signed-off-by: Gerard Marull-Paretas <[email protected]>

Author: gmarull

doc/nrf/conf.py

@@ -41,7 +41,6 @@
     "manifest_revisions_table",
     "sphinxcontrib.mscgen",
     "zephyr.html_redirects",
-    "zephyr.warnings_filter",
     "zephyr.kconfig",
     "zephyr.external_content",
     "zephyr.doxyrunner",
@@ -165,10 +164,6 @@
 
 html_redirect_pages = redirects.NRF
 
-# -- Options for zephyr.warnings_filter ----------------------------------------
-
-warnings_filter_config = str(NRF_BASE / "doc" / "nrf" / "known-warnings.txt")
-
 # Options for zephyr.link-roles ------------------------------------------------
 
 link_roles_manifest_project = "nrf"