sparc,kgdbts: fix compile regression with kgdb test suite

Commit 63ab25ebbc (kgdbts: unify/generalize gdb breakpoint adjustment)
introduced a compile regression on sparc.

kgdbts.c: In function 'check_and_rewind_pc':
kgdbts.c:307: error: implicit declaration of function 'instruction_pointer_set'

Simply add the correct macro definition for instruction pointer on the
Sparc architecture.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: David S. Miller <davem@davemloft.net>

arch/sparc/include/asm/ptrace.h

@@ -205,6 +205,7 @@ do {	current_thread_info()->syscall_noerror = 1; \
 } while (0)
 #define user_mode(regs) (!((regs)->tstate & TSTATE_PRIV))
 #define instruction_pointer(regs) ((regs)->tpc)
+#define instruction_pointer_set(regs, val) ((regs)->tpc = (val))
 #define user_stack_pointer(regs) ((regs)->u_regs[UREG_FP])
 #define regs_return_value(regs) ((regs)->u_regs[UREG_I0])
 #ifdef CONFIG_SMP