Fixing protoOutParams concatenation.

ParseGeneratorParameter delimits based on commas, not colons:
external/protobuf/src/google/protobuf/compiler/code_generator.cc

Bug: 72570104
Test: flash device with new build
Change-Id: I00042782a718d288ca6b0cb78f856d0fb223a926
diff --git a/cc/proto.go b/cc/proto.go
index c53dcf4..42bb536 100644
--- a/cc/proto.go
+++ b/cc/proto.go
@@ -115,7 +115,7 @@
 	flags.protoFlags = android.ProtoFlags(ctx, p)
 
 	if proptools.String(p.Proto.Type) == "lite" {
-		flags.protoOutParams = []string{"lite"}
+		flags.protoOutParams = append(flags.protoOutParams, "lite")
 	}
 
 	return flags