io timers: fix some typos

src/drivers/drv_pwm_output.h

@@ -363,7 +363,7 @@ __EXPORT extern int	up_pwm_servo_set_rate_group_update(unsigned group, unsigned
 /**
  * Trigger all timer's channels in Oneshot mode to fire
  * the oneshot with updated values.
- * Nothing is none if not in oneshot mode.
+ * Nothing is done if not in oneshot mode.
  *
  */
 __EXPORT extern void up_pwm_update(void);

src/drivers/stm32/drv_io_timer.c

@@ -502,7 +502,7 @@ void io_timer_trigger(void)
 			}
 		}
 
-		/* Now do them all wit the shortest delay in between */
+		/* Now do them all with the shortest delay in between */
 
 		irqstate_t flags = px4_enter_critical_section();