ci: fix path to Baseband_guard Makefile in build workflow

The path to the Makefile was incorrect, pointing to the root directory instead of the common directory. This ensures the kernel config symbols are properly included during the build process.

.github/workflows/build.yml

@@ -272,7 +272,7 @@ jobs:
           wget -O- https://github.com/vc-teahouse/Baseband-guard/raw/main/setup.sh | bash
           echo "CONFIG_BBG=y" >> common/arch/arm64/configs/gki_defconfig
           sed -i '/^config LSM$/,/^help$/{ /^[[:space:]]*default/ { /baseband_guard/! s/landlock/landlock,baseband_guard/ } }' common/security/Kconfig
-          sed -i '/^obj-\$$(CONFIG_BBG) += baseband_guard.o/i # Include kernel config symbols (safe point)\n-include $(srctree)/include/config/auto.conf' Baseband_guard/Makefile
+          sed -i '/^obj-\$$(CONFIG_BBG) += baseband_guard.o/i # Include kernel config symbols (safe point)\n-include $(srctree)/include/config/auto.conf' common/Baseband_guard/Makefile
 
       - name: Apply Module Check Bypass
         if: ${{ matrix.apply_module_check_bypass == 'bypass' }}