platform/x86: dell-laptop: Refactor kbd_led_triggers_store()

Return -EINVAL immediately on invalid input, rather then doing
the straight path in an if block and returning -EINVAL at the end
of the function.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

drivers/platform/x86/dell-laptop.c

@@ -1666,15 +1666,19 @@ static ssize_t kbd_led_triggers_store(struct device *dev,
 		}
 	}
 
-	if (trigger_bit != -1) {
+	if (trigger_bit == -1)
+		return -EINVAL;
+
 	new_state = state;
 	if (trigger[0] == '+')
 		new_state.triggers |= BIT(trigger_bit);
 	else {
 		new_state.triggers &= ~BIT(trigger_bit);
-			/* NOTE: trackstick bit (2) must be disabled when
+		/*
+		 * NOTE: trackstick bit (2) must be disabled when
 		 *       disabling touchpad bit (1), otherwise touchpad
-			 *       bit (1) will not be disabled */
+		 *       bit (1) will not be disabled
+		 */
 		if (trigger_bit == 1)
 			new_state.triggers &= ~BIT(2);
 	}
@@ -1695,9 +1699,6 @@ static ssize_t kbd_led_triggers_store(struct device *dev,
 	if (new_state.mode_bit != KBD_MODE_BIT_OFF)
 		kbd_previous_mode_bit = new_state.mode_bit;
 	return count;
-	}
-
-	return -EINVAL;
 }
 
 static ssize_t kbd_led_triggers_show(struct device *dev,