drivers: nrf_rtc_timer: Check channel bit when handling force_isr_mask

Add missing masking against `BIT(chan)` when handling a forced ISR
to avoid unnecessary processing of multiple channels instead of just
the one that actually requires it.

Signed-off-by: Andrzej Głąbek <[email protected]>

Author: anangl

drivers/timer/nrf_rtc_timer.c

@@ -428,7 +428,7 @@ static bool channel_processing_check_and_clear(int32_t chan)
 		/* The processing of channel can be caused by CC match
 		 * or be forced.
 		 */
-		result = atomic_and(&force_isr_mask, ~BIT(chan)) ||
+		result = (atomic_and(&force_isr_mask, ~BIT(chan)) & BIT(chan)) ||
 			 event_check(chan);
 
 		if (result) {