[PATCH] tools/perf: fix build when WERROR=1

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

util/symbol.c: In function ‘hex2u64’:
util/symbol.c:2836:2: error: passing argument 2 of ‘strtoull’ from incompatible pointer type [-Werror]
In file included from util/symbol.c:3:0:
/usr/include/stdlib.h:215:31: note: expected ‘char ** restrict’ but argument is of type ‘const char **’
cc1: all warnings being treated as errors
make[1]: *** [util/symbol.o] Error 1
make[1]: Leaving directory `/home/andy/prj/linux-2.6/tools/perf'
make: *** [perf] Error 2

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 tools/perf/util/symbol.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index ba2a489..26e695c 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -2831,7 +2831,7 @@ int machines__create_kernel_maps(struct rb_root *machines, pid_t pid)
  */
 int hex2u64(const char *ptr, u64 *long_val)
 {
-	const char *p = ptr;
+	char *p;
 
 	*long_val = strtoull(ptr, &p, 16);
 
-- 
1.7.10.4