gn2bp: fix collecting static libs dependencies

There were some flaws in the previous logic. Dependencies need to be
bubbled up for all targets, but only static_libs should be added to
them.

Test: update_results.sh
Change-Id: I98025a8a0720d34bc47a820bf45118c06acd64a0
diff --git a/tools/gn2bp/gen_android_bp b/tools/gn2bp/gen_android_bp
index b99a559..4bd2479 100755
--- a/tools/gn2bp/gen_android_bp
+++ b/tools/gn2bp/gen_android_bp
@@ -155,7 +155,7 @@
 def enable_protoc_lib(module):
   if module.type == 'cc_binary_host':
     module.static_libs.add('libprotoc')
-  else:
+  elif module.type not in ['genrule', 'filegroup']:
     module.shared_libs.add('libprotoc')