AK3: add option to skip vbmeta patching while avb is enabled (#90)

Signed-off-by: engstk <eng.stk@sapo.pt>

META-INF/com/google/android/updater-script

@@ -3,4 +3,4 @@
 # Dummy file; update-binary is a shell script (DO NOT CHANGE)
 #
 #
-# AK_BASE_VERSION=20241012
+# AK_BASE_VERSION=20241014

README.md

@@ -61,6 +61,8 @@ __supported.patchlevels=__ and __supported.vendorpatchlevels=__ will match again
 
 `NO_MAGISK_CHECK=1` may be added to disable detection of Magisk and related kernel/dtb repatching for special zips which don't require that.
 
+`NO_VBMETA_PARTITION_PATCH=1` may be added to skip vbmeta processing using httools, since GKI is bootable with verity/verification ON, as long as AVB is not enforced for boot stage partitions.
+
 ## // Command Methods ##
 ```
 ui_print "<text>" [...]

tools/ak3-core.sh

@@ -483,7 +483,7 @@ flash_generic() {
     if [ "$path" == "/dev/block/mapper" ]; then
       avb=$(httools_static avb $1);
       [ $? == 0 ] || abort "Failed to parse fstab entry for $1. Aborting...";
-      if [ "$avb" ]; then
+      if [ "$avb" ] && [ ! "$NO_VBMETA_PARTITION_PATCH" ]; then
         flags=$(httools_static disable-flags);
         [ $? == 0 ] || abort "Failed to parse top-level vbmeta. Aborting...";
         if [ "$flags" == "enabled" ]; then