Fix a few non-dash safe xstormy16 shell scripts.

Fix a few non-dash safe xstormy16 shell scripts.

Noticed by a customer while looking at a tangentially related problem.  The
gas testsuite for xstormy16 has two scripts that have a typo on the first
line, they are missing the !.  They also use shell syntax that doesn't work
on a system where /bin/sh is dash.  So I fixed the typo, changed the shell
to bash, and made them executable, so that they now work when run directly
even if /bin/sh is dash.

	gas/
	* testsuite/gas/xstormy16/allinsn.sh: Change first line to
	#!/bin/bash and make it executable.
	* testsuite/gas/xstormy16/gcc.sh: Likewise.