Renderscript: rename .rs extension to .rscript

Reserve .rs extension for Rust.

Bug: 137365032
Test: make checkbuild
Test: cd frameworks/compile/slang/tests
    ./slang_tests.py
    Test: atest CtsRenderscriptTestCases
    Test: CtsRsCppTestCases

Change-Id: I0458009b8bb64a012fece364835d5b78d52e15e9
Merged-In: I0458009b8bb64a012fece364835d5b78d52e15e9
diff --git a/cc/gen.go b/cc/gen.go
index c9f45ee..1d5cc48 100644
--- a/cc/gen.go
+++ b/cc/gen.go
@@ -237,7 +237,7 @@
 			depFile := android.GenPathWithExt(ctx, "aidl", srcFile, "cpp.d")
 			srcFiles[i] = cppFile
 			deps = append(deps, genAidl(ctx, aidlRule, srcFile, cppFile, depFile, buildFlags.aidlFlags)...)
-		case ".rs", ".fs":
+		case ".rscript", ".fs":
 			cppFile := rsGeneratedCppFile(ctx, srcFile)
 			rsFiles = append(rsFiles, srcFiles[i])
 			srcFiles[i] = cppFile