selftests/powerpc: Give the bad_accesses test longer to run

On older systems this test takes longer to run (duh), give it five
minutes which is long enough on a G5 970FX @ 1.6GHz.

Signed-off-by: Michael Ellerman <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

tools/testing/selftests/powerpc/mm/bad_accesses.c

···
 
 int main(void)
 {
+	test_harness_set_timeout(300);
 	return test_harness(test, "bad_accesses");
 }