Improve selection of target_cpu in android_gdbserver

Change-Id: I44ed5306155af089fab6d97b0e2108e637c46d63
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/284732
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
1 file changed