GDB looks for specific opcode sequences when trying to recognize a stack
frame as a signal trampoline. The sequences it looks for happen to be those
created when SA_RESTORER is set, since glibc always sets a restorer. This
patch does the same here, so that the trampolines can be correctly identified.
Change-Id: I0ac574a68818cb24d939c3527f3aaeb04b853d04
