gn2bp: remove perfetto build flags file

Test: n/a
Change-Id: I6a6066e41749379733da8df420b30a2017724cf2
diff --git a/tools/gn2bp/gen_android_bp b/tools/gn2bp/gen_android_bp
index b7e2e6b..438d0f2 100755
--- a/tools/gn2bp/gen_android_bp
+++ b/tools/gn2bp/gen_android_bp
@@ -1109,10 +1109,6 @@
     # Text files should have a trailing EOL.
     f.write('\n')
 
-  # Generate the perfetto_build_flags.h file.
-  out_files.append(os.path.join(buildflags_dir, 'perfetto_build_flags.h.swp'))
-  gn_utils.gen_buildflags(gn_args, out_files[-1])
-
   return 0