Introduce vintf_fragment module type

Introduce a new vintf_fragment module type which handles vintf_fragment
files within Soong. This will help process to move vintf_fragment
handling logic from KATI to Soong. This change also introduces
vintf_fragment_modules property to mark dependency with vintf_fragment
modules.

Bug: 322089980
Test: m nothing --no-skip-soong-tests passed
Change-Id: I49607f42aeee3ded0ba7b078b903dc35f5d61637
diff --git a/apex/apex.go b/apex/apex.go
index fc0500a..dd1c0b5 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -2370,6 +2370,7 @@
 	a.providePrebuiltInfo(ctx)
 
 	a.required = a.RequiredModuleNames(ctx)
+	a.required = append(a.required, a.VintfFragmentModuleNames(ctx)...)
 
 	a.setOutputFiles(ctx)
 }