manifest: Track our own fork(s) for 2023-10 ASB patching

* external/libxml2

Author: Meghthedev

default.xml

@@ -306,7 +306,7 @@
   <project path="external/libvterm" name="platform/external/libvterm" groups="pdk" remote="aosp" />
   <project path="external/libxaac" name="platform/external/libxaac" groups="pdk" remote="aosp" />
   <project path="external/libxkbcommon" name="platform/external/libxkbcommon" groups="pdk" remote="aosp" />
-  <project path="external/libxml2" name="platform/external/libxml2" groups="pdk,libxml2" remote="aosp" />
+  <project path="external/libxml2" name="LineageOS/external_libxml2" groups="pdk,libxml2" />
   <project path="external/libyuv" name="platform/external/libyuv" groups="pdk,libyuv" remote="aosp" />
   <project path="external/linux-kselftest" name="platform/external/linux-kselftest" groups="vts,pdk" clone-depth="1" remote="aosp" />
   <project path="external/llvm" name="platform/external/llvm" groups="pdk" remote="aosp" />