x86: Rename CONFIG_SYS_NUM_IRQS to SYS_NUM_IRQS

CONFIG_SYS_NUM_IRQS is actually not something we can configure,
but an architecture defined number of ISA IRQs. Move it from
x86-common.h to asm/interrupt.h and rename it to SYS_NUM_IRQS.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/lib/pcat_interrupts.c b/arch/x86/lib/pcat_interrupts.c
index a9af87e..3704aaf 100644
--- a/arch/x86/lib/pcat_interrupts.c
+++ b/arch/x86/lib/pcat_interrupts.c
@@ -20,10 +20,6 @@
 #include <asm/ibmpc.h>
 #include <asm/interrupt.h>
 
-#if CONFIG_SYS_NUM_IRQS != 16
-#error "CONFIG_SYS_NUM_IRQS must equal 16 if CONFIG_SYS_NUM_IRQS is defined"
-#endif
-
 int i8259_init(void)
 {
 	u8 i;
@@ -70,7 +66,7 @@
 {
 	int imr_port;
 
-	if (irq >= CONFIG_SYS_NUM_IRQS)
+	if (irq >= SYS_NUM_IRQS)
 		return;
 
 	if (irq > 7)
@@ -85,7 +81,7 @@
 {
 	int imr_port;
 
-	if (irq >= CONFIG_SYS_NUM_IRQS)
+	if (irq >= SYS_NUM_IRQS)
 		return;
 
 	if (irq > 7)
@@ -98,7 +94,7 @@
 
 void specific_eoi(int irq)
 {
-	if (irq >= CONFIG_SYS_NUM_IRQS)
+	if (irq >= SYS_NUM_IRQS)
 		return;
 
 	if (irq > 7) {