patch 9.0.1541: CI: sound dummy is disabled

Problem:    CI: sound dummy is disabled.
Solution:   Make sound dummy work again. (closes #12380)
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6d50f8c..207b7dd 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -174,18 +174,21 @@
           sudo usermod -a -G audio "${USER}"
           sudo bash ci/setup-xvfb.sh
 
-      # FIXME: Temporarily disabled because of build errors
-      # - name: Set up snd-dummy
-      #   if: (!(contains(matrix.extra, 'unittests') || contains(matrix.extra, 'vimtags')))
-      #   env:
-      #     DEST_DIR: ${{ env.TMPDIR }}/linux-modules-extra-${{ env.LINUX_VERSION }}
-      #   run: |
-      #     cd /lib/modules/${{ env.LINUX_VERSION }}
-      #     sudo apt-get install -d -y linux-modules-extra-${{ env.LINUX_VERSION }}
-      #     sudo dpkg -x /var/cache/apt/archives/linux-modules-extra-${{ env.LINUX_VERSION }}*.deb "${DEST_DIR}"
-      #     tar -cC "${DEST_DIR}"/lib/modules/${{ env.LINUX_VERSION }} kernel/sound | sudo tar -x
-      #     sudo depmod
-      #     sudo modprobe snd-dummy
+      - name: Set up snd-dummy
+        if: (!(contains(matrix.extra, 'unittests') || contains(matrix.extra, 'vimtags')))
+        env:
+          DEST_DIR: ${{ env.TMPDIR }}/linux-modules-extra-${{ env.LINUX_VERSION }}
+        run: |
+          cd /lib/modules/${{ env.LINUX_VERSION }}
+          if [ sudo apt-get install -d -y linux-modules-extra-${{ env.LINUX_VERSION }} 2>&1 | $(grep "Unable to locate package ") ]; then
+          echo "Download of " linux-modules-extra-${{ env.LINUX_VERSION }} "failed continue anyway" exit 0
+          else
+          sudo apt-get install -d -y linux-modules-extra-${{ env.LINUX_VERSION }}
+          sudo dpkg -x /var/cache/apt/archives/linux-modules-extra-${{ env.LINUX_VERSION }}*.deb "${DEST_DIR}"
+          tar -cvC "${DEST_DIR}"/lib/modules/${{ env.LINUX_VERSION }} kernel/sound | sudo tar -x
+          sudo depmod --verbose
+          sudo modprobe --verbose snd-dummy
+          fi
 
       - name: Check autoconf
         if: contains(matrix.extra, 'unittests')
diff --git a/src/version.c b/src/version.c
index e5f4afa..c917be5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1541,
+/**/
     1540,
 /**/
     1539,