package/gdb: backport upstream fix for simulator build issue with bfin

package/gdb: backport upstream fix for simulator build issue with bfin

This revert the commit [1] which break the simulator for aarch64.
Backport the upstream fix instead (from 7.12).

[1] f71ad71f24fbeca1a81cc9efe79016a7db6f1320

Tested with gcc 4.4.5 (debian squeeze chroot).

Fixes:
http://autobuild.buildroot.net/results/cfd/cfdc9117fef7ecdf5cc5fc907a6fe8701a2c174a

Signed-off-by: Romain Naour <romain.naour@gmail.com>
Cc: Waldemar Brodkorb <wbx@openadk.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>