parisc: add task_pt_regs macro

needed for perf_counters.
Signed-off-by: NKyle McMartin <kyle@mcmartin.ca>

arch/parisc/include/asm/processor.h

@@ -18,6 +18,7 @@
 #include <asm/types.h>
 #include <asm/system.h>
 #include <asm/percpu.h>
+
 #endif /* __ASSEMBLY__ */
 
 #define KERNEL_STACK_SIZE 	(4*PAGE_SIZE)
@@ -127,6 +128,8 @@ struct thread_struct {
 	unsigned long  flags;
 }; 
 
+#define task_pt_regs(tsk) ((struct pt_regs *)&((tsk)->thread.regs))
+
 /* Thread struct flags. */
 #define PARISC_UAC_NOPRINT	(1UL << 0)	/* see prctl and unaligned.c */
 #define PARISC_UAC_SIGBUS	(1UL << 1)