Add support for no-vendor-variant VNDK

When no-vendor-variant VNDK is enabled, the vendor variant of VNDK
libraries are not installed.  Since not all VNDK libraries will be
ready for this, we keep a list of library names in cc/vndk.go to
indicate which libraries must have their vendor variants always
installed regardless of whether no-vendor-variant VNDK is enabled.

Also add --remove-build-id option to the strip script to facilitate
the check of functional identity of the two variants.

Bug: 119423884
Test: Add a dummy VNDK library and build with
      TARGET_VNDK_USE_CORE_VARIANT := true, with the corresponding
      build/make change.

Change-Id: Ieb1589488690e1cef1e310669a8b47a8b8759dac
diff --git a/cc/makevars.go b/cc/makevars.go
index 4a9ade2..aa6fdea 100644
--- a/cc/makevars.go
+++ b/cc/makevars.go
@@ -97,6 +97,7 @@
 	ctx.Strict("VNDK_SAMEPROCESS_LIBRARIES", strings.Join(vndkSpLibraries, " "))
 	ctx.Strict("LLNDK_LIBRARIES", strings.Join(llndkLibraries, " "))
 	ctx.Strict("VNDK_PRIVATE_LIBRARIES", strings.Join(vndkPrivateLibraries, " "))
+	ctx.Strict("VNDK_USING_CORE_VARIANT_LIBRARIES", strings.Join(vndkUsingCoreVariantLibraries, " "))
 
 	// Filter vendor_public_library that are exported to make
 	exportedVendorPublicLibraries := []string{}