tools/memory-model: Make runlitmus.sh check for jingle errors

It turns out that the jingle7 tool is currently a bit picky about
the litmus tests it is willing to process. This commit therefore
ensures that jingle7 failures are reported.

Signed-off-by: Paul E. McKenney <[e-mail]>

tools/memory-model/scripts/runlitmus.sh

···
 # Generate the assembly code and run herd7 on it.
 gen_theme7 -n 10 -map $mapfile -call Linux.call > $themefile
 jingle7 -theme $themefile $litmus > $LKMM_DESTDIR/$hwlitmus 2> $T/$hwlitmusfile.jingle7.out
+if grep -q "Generated 0 tests" $T/$hwlitmusfile.jingle7.out
+then
+	echo ' !!! ' jingle7 failed, no $hwlitmus generated
+	exit 253
+fi
 /usr/bin/time $LKMM_TIMEOUT_CMD herd7 $LKMM_DESTDIR/$hwlitmus > $LKMM_DESTDIR/$hwlitmus.out 2>&1
 
 exit $?