perf: Use strcmp(str, "const") instead of strncmp(str, "const", sizeof("const"))

[Steven Rostedt]

As strncmp(str, "const", sizeof("const") is exactly the same as
strcmp(str, "const") use that instead, otherwise it is confusing.

sizeof("const") includes the nul terminator ('\0') of the string
"const", and that means strncmp() will only return a match if str and
"const" are exactly the same, which is what strcmp() does.

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 32ef7bdca1cf..eabf30f963a5 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -258,7 +258,7 @@ int parse_callchain_record(const char *arg, struct callchain_param *param)
 
 	do {
 		/* Framepointer style */
-		if (!strncmp(name, "fp", sizeof("fp"))) {
+		if (!strcmp(name, "fp")) {
 			if (!strtok_r(NULL, ",", &saveptr)) {
 				param->record_mode = CALLCHAIN_FP;
 				ret = 0;
@@ -268,7 +268,7 @@ int parse_callchain_record(const char *arg, struct callchain_param *param)
 			break;
 
 		/* Dwarf style */
-		} else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
+		} else if (!strcmp(name, "dwarf")) {
 			const unsigned long default_stack_dump_size = 8192;
 
 			ret = 0;