tests: spin lock timeout test spin time

The spin loop to ensure time goes past the timeout is done in terms
of the core clock, while the spin lock is timed on the system clock.

This difference is exasperated on systems where the core clock is much
faster than the system clock and the test failed. Add a significant
multiplier so the test works even when the system clock is much slower.

Signed-off-by: Tom Burdick <thomas.burdick@intel.com>

tests/kernel/spinlock/src/spinlock_error_case.c

@@ -173,8 +173,11 @@ ZTEST(spinlock, test_spinlock_lock_time_limit)
 
 	key = k_spin_lock(&timeout_lock);
 
-	/* spin here for at least 2x the cycle limit */
-	for (volatile int i = 0; i < CONFIG_SPIN_LOCK_TIME_LIMIT*2; i++) {
+	/* spin here a while, the spin lock limit is in terms of system clock
+	 * not core clock. So a multiplier is needed here to ensure things
+	 * go well past the time limit.
+	 */
+	for (volatile int i = 0; i < CONFIG_SPIN_LOCK_TIME_LIMIT*10; i++) {
 	}
 
 	set_assert_valid(true, false);