perf unwind: Fix wrongly used regs for x86_32 unwind

By default, "unwind-libunwind-local.c" gets SP/IP register number
according to the host platform, for remote unwind, we should use
register number for target platform. Fix this by define
LIBUNWIND_ARCH_REG_SP/IP in the wrapper file of x86_32 platform.

Signed-off-by: He Kuang <[e-mail]>
Acked-by: Jiri Olsa <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: David Ahern <[e-mail]>
Cc: Ekaterina Tumanova <[e-mail]>
Cc: Josh Poimboeuf <[e-mail]>
Cc: Kan Liang <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Pekka Enberg <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Stephane Eranian <[e-mail]>
Cc: Sukadev Bhattiprolu <[e-mail]>
Cc: Wang Nan <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/libunwind/x86_32.c

···
  */
 
 #define REMOTE_UNWIND_LIBUNWIND
+
+/* Define arch specific functions & regs for libunwind, should be
+ * defined before including "unwind.h"
+ */
 #define LIBUNWIND__ARCH_REG_ID(regnum) libunwind__x86_reg_id(regnum)
+#define LIBUNWIND__ARCH_REG_IP PERF_REG_X86_IP
+#define LIBUNWIND__ARCH_REG_SP PERF_REG_X86_SP
 
 #include "unwind.h"
 #include "debug.h"