Update some comments

sched/sched/sched_lock.c

@@ -151,7 +151,7 @@ int sched_lock(void)
 
   if (rtcb && !up_interrupt_context())
     {
-      /* Catch attempts to increment the lockcount beyound the range of the
+      /* Catch attempts to increment the lockcount beyond the range of the
        * integer type.
        */
 

sched/sched/sched_unlock.c

@@ -101,7 +101,7 @@ int sched_unlock(void)
       if (rtcb->lockcount <= 0)
         {
 #ifdef CONFIG_SCHED_INSTRUMENTATION_PREEMPTION
-          /* Note that we no longer have pre-emption */
+          /* Note that we no longer have pre-emption disabled. */
 
           sched_note_premption(rtcb, false);
 #endif

sched/semaphore/spinlock.c

@@ -468,7 +468,7 @@ void spin_setbit(FAR volatile cpu_set_t *set, unsigned int cpu,
   irqstate_t flags;
 
   /* Disable local interrupts to prevent being re-entered from an interrupt
-   * on the same CPU.  This does not effect the behavior on other CPUs.
+   * on the same CPU.  This may not effect interrupt behavior on other CPUs.
    */
 
   flags = up_irq_save();
@@ -527,7 +527,7 @@ void spin_clrbit(FAR volatile cpu_set_t *set, unsigned int cpu,
   irqstate_t flags;
 
   /* Disable local interrupts to prevent being re-entered from an interrupt
-   * on the same CPU.  This does not effect the behavior on other CPUs.
+   * on the same CPU.  This may not effect interrupt behavior on other CPUs.
    */
 
   flags = up_irq_save();