compiler_wrapper: make the update script not die on missing packages

Fresh chroots might not have all of these GCCs emerged. Just `continue`
if that's not the case.

This also fixes failing lints.

BUG=None
TEST=Ran the script

Change-Id: I57a2ca72dfbaea324ddb66423294e1b4dd8989e1
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2080660
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Tested-by: George Burgess <gbiv@chromium.org>
1 file changed