AOSP Music to bazel: path added to bazel.go

In order to reconcile the mixed builds between
Soong and Bazel, the path for the AOSP Music
BUILD file must be added to the bp2buildKeepExistingBuildFile
map.

Change-Id: Ib895d0f4a09502da2d33fc673026d91269b4d086
diff --git a/android/bazel.go b/android/bazel.go
index 46212dc..d40e650 100644
--- a/android/bazel.go
+++ b/android/bazel.go
@@ -140,6 +140,7 @@
 
 		"prebuilts/sdk":/* recursive = */ false,
 		"prebuilts/sdk/tools":/* recursive = */ false,
+		"packages/apps/Music":/* recursive = */ false,
 	}
 
 	// Configure modules in these directories to enable bp2build_available: true or false by default.