tests: Increase verbosity in *_test.in checks

In this case it does not hurt to increase bash execution verbosity so
we can get more insight in case of issues.

Signed-off-by: Leo Sandoval <lsandova@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

tests/pseries_test.in

@@ -14,7 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
 
-set -e
+set -ex
 grubshell=@builddir@/grub-shell
 
 . "@builddir@/grub-core/modinfo.sh"