boards, include, sched: Remove CONFIG_SPINLOCK_IRQ

Summary:
- This commit removes CONFIG_SPINLOCK_IRQ to avoid complexity

Impact:
- None

Testing:
- Tested with the following configs
- spresense:wifi, spresense:smp
- esp32-devkitc:smp (QEMU), sabre-6quad:smp (QEMU)
- maix-bit:smp (QEMU), sim:smp
- stm32f4discovery:wifi

include/nuttx/irq.h

@@ -273,7 +273,7 @@ void leave_critical_section(irqstate_t flags);
  * Name: spin_lock_irqsave
  *
  * Description:
- *   If SMP and SPINLOCK_IRQ are enabled:
+ *   If SMP is are enabled:
  *     Disable local interrupts and take the global spinlock (g_irq_spin)
  *     if the call counter (g_irq_spin_count[cpu]) equals to 0. Then the
  *     counter on the CPU is increment to allow nested call.
@@ -282,7 +282,7 @@ void leave_critical_section(irqstate_t flags);
  *     or internal data structure) in SMP mode. But do not use this API
  *     with kernel APIs which suspend a caller thread. (e.g. nxsem_wait)
  *
- *   If SMP and SPINLOCK_IRQ are not enabled:
+ *   If SMP is not enabled:
  *     This function is equivalent to enter_critical_section().
  *
  * Input Parameters:
@@ -294,7 +294,7 @@ void leave_critical_section(irqstate_t flags);
  *
  ****************************************************************************/
 
-#if defined(CONFIG_SMP) && defined(CONFIG_SPINLOCK_IRQ)
+#if defined(CONFIG_SMP)
 irqstate_t spin_lock_irqsave(void);
 #else
 #  define spin_lock_irqsave() enter_critical_section()
@@ -304,13 +304,13 @@ irqstate_t spin_lock_irqsave(void);
  * Name: spin_unlock_irqrestore
  *
  * Description:
- *   If SMP and SPINLOCK_IRQ are enabled:
+ *   If SMP is enabled:
  *     Decrement the call counter (g_irq_spin_count[cpu]) and if it
  *     decrements to zero then release the spinlock (g_irq_spin) and
  *     restore the interrupt state as it was prior to the previous call to
  *     spin_lock_irqsave().
  *
- *   If SMP and SPINLOCK_IRQ are not enabled:
+ *   If SMP is not enabled:
  *     This function is equivalent to leave_critical_section().
  *
  * Input Parameters:
@@ -322,7 +322,7 @@ irqstate_t spin_lock_irqsave(void);
  *
  ****************************************************************************/
 
-#if defined(CONFIG_SMP) && defined(CONFIG_SPINLOCK_IRQ)
+#if defined(CONFIG_SMP)
 void spin_unlock_irqrestore(irqstate_t flags);
 #else
 #  define spin_unlock_irqrestore(f) leave_critical_section(f)