Revert "subtree updates"

Needs to go through CI

This reverts commit fc7e7973f3119e2bad511209aa336537dc5ffbed.
diff --git a/meta-raspberrypi/.github/workflows/docker-images/yocto-builder/entrypoint-build.sh b/meta-raspberrypi/.github/workflows/docker-images/yocto-builder/entrypoint-build.sh
index 65999d0..d2c6dc0 100755
--- a/meta-raspberrypi/.github/workflows/docker-images/yocto-builder/entrypoint-build.sh
+++ b/meta-raspberrypi/.github/workflows/docker-images/yocto-builder/entrypoint-build.sh
@@ -42,9 +42,7 @@
 cat <<EOCONF >>conf/local.conf
 BB_NUMBER_THREADS = "6"
 PARALLEL_MAKE = "-j 6"
-# unmerged-usr is deprecated
-# https://lore.kernel.org/all/3f2f03085301d22854e5429019fb010f27d98bc7.camel@linuxfoundation.org/t/
-DISTRO_FEATURES:append = " systemd usrmerge"
+DISTRO_FEATURES:append = " systemd"
 VIRTUAL-RUNTIME_init_manager = "systemd"
 DISTRO_FEATURES_BACKFILL_CONSIDERED:append = " sysvinit"
 VIRTUAL-RUNTIME_initscripts = "systemd-compat-units"
diff --git a/meta-raspberrypi/docs/conf.py b/meta-raspberrypi/docs/conf.py
index 39e7223..e7a2491 100644
--- a/meta-raspberrypi/docs/conf.py
+++ b/meta-raspberrypi/docs/conf.py
@@ -30,10 +30,7 @@
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
-extensions = [
-    'myst_parser',
-    'sphinx_rtd_theme'
-]
+extensions = ['myst_parser']
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']
@@ -124,7 +121,6 @@
 # a list of builtin themes.
 #
 # html_theme = 'alabaster'
-html_theme = "sphinx_rtd_theme"
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
diff --git a/meta-raspberrypi/docs/requirements.txt b/meta-raspberrypi/docs/requirements.txt
index 51eebd0..9e4694f 100644
--- a/meta-raspberrypi/docs/requirements.txt
+++ b/meta-raspberrypi/docs/requirements.txt
@@ -1,2 +1 @@
 myst_parser
-sphinx_rtd_theme
diff --git a/meta-raspberrypi/recipes-multimedia/omxplayer/omxplayer_git.bb b/meta-raspberrypi/recipes-multimedia/omxplayer/omxplayer_git.bb
index b7eaf40..b43a41f 100644
--- a/meta-raspberrypi/recipes-multimedia/omxplayer/omxplayer_git.bb
+++ b/meta-raspberrypi/recipes-multimedia/omxplayer/omxplayer_git.bb
@@ -11,8 +11,6 @@
 
 PR = "r6"
 
-SRCREV_FORMAT = "_ffmpeg"
-
 SRCREV_default = "1f1d0ccd65d3a1caa86dc79d2863a8f067c8e3f8"
 
 # omxplayer builds its own copy of ffmpeg from source instead of using the