Remove GDB patches

The remaining patches are currently not actively used, and unlikely
to be used again in the future.

Change-Id: Ie2cc47d5076f5e28b8182c0ff06621f576c81d34
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Reviewed-by: David Schulz <david.schulz@digia.com>
Reviewed-by: Rainer Keller <rainer.keller@digia.com>