Define step-0 for vintf finalization

Define `vintf` state that have completed vintf finalization only.
Only if FINAL_STATE is 'unfinalized' run the vintf finalization
process to finalize vintf.
The new step-0 only runs the vintf finalization.

Ignore-AOSP-First: trunk-stable changes (b/304316873)

Bug: 318883690
Test: build-step-0.sh && build/soong/soong_ui.bash \
    --make-mode TARGET_PRODUCT=cf_x86_64_phone TARGET_RELEASE=fina_0 \
    TARGET_BUILD_VARIANT=userdebug droid dist
Change-Id: If3525f38204fa546744b9ccf8dc9e63711823abd

tools/finalization/build-step-1-and-2.sh

@@ -7,12 +7,16 @@ function finalize_main_step12() {
     source $top/build/make/tools/finalization/environment.sh
 
     if [ "$FINAL_STATE" = "unfinalized" ] ; then
-        # SDK codename -> int
+        # VINTF finalization
         source $top/build/make/tools/finalization/finalize-vintf-resources.sh
+    fi;
+
+    if [ "$FINAL_STATE" = "unfinalized" ] || [ "$FINAL_STATE" = "vintf" ] ; then
+        # SDK codename -> int
         source $top/build/make/tools/finalization/finalize-sdk-resources.sh
     fi;
 
-    if [ "$FINAL_STATE" = "unfinalized" ] || [ "$FINAL_STATE" = "sdk" ] ; then
+    if [ "$FINAL_STATE" = "unfinalized" ] || [ "$FINAL_STATE" = "vintf" ] || [ "$FINAL_STATE" = "sdk" ] ; then
         # ADB, Platform/Mainline SDKs build and move to prebuilts
         source $top/build/make/tools/finalization/localonly-steps.sh