fix spelling errors

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1699 bbd45198-f89e-11dd-88c7-29a3b14d5316

libcpu/mips/pic32/context_gcc.S

@@ -55,17 +55,17 @@ rt_hw_context_switch:
 /*
  * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to)/*
  */
-    .globl rt_thread_switch_interrput_flag
+    .globl rt_thread_switch_interrupt_flag
     .globl rt_interrupt_from_thread
     .globl rt_interrupt_to_thread
     .globl rt_hw_context_switch_interrupt
 rt_hw_context_switch_interrupt:
-    la      t0, rt_thread_switch_interrput_flag
+    la      t0, rt_thread_switch_interrupt_flag
     lw      t1, 0(t0)
     nop
     bnez    t1, _reswitch
     nop
-    li      t1, 0x01                       /* set rt_thread_switch_interrput_flag to 1 */
+    li      t1, 0x01                       /* set rt_thread_switch_interrupt_flag to 1 */
     sw      t1, 0(t0)
     la      t0, rt_interrupt_from_thread   /* set rt_interrupt_from_thread */
     sw      a0, 0(t0)
@@ -100,7 +100,7 @@ CoreSW0Handler:
 	addiu   t1,zero,0x02            /* t1 = (1<<2) */
 	sw      t1, 0(t0)               /* IFS0CLR = t1 */
 
-    la      k0, rt_thread_switch_interrput_flag
+    la      k0, rt_thread_switch_interrupt_flag
     sw      zero, 0(k0)                     /* clear flag */
 
     /*

libcpu/mips/pic32/cpuport.c

@@ -21,7 +21,7 @@
 
 /* exception and interrupt handler table */
 rt_uint32_t rt_interrupt_from_thread, rt_interrupt_to_thread;
-rt_uint32_t rt_thread_switch_interrput_flag;
+rt_uint32_t rt_thread_switch_interrupt_flag;
 
 rt_uint32_t __attribute__((nomips16)) _get_gp(void)
 {