perf probe: Fix strtailcmp() to compare s1and s2[0]

Fix strtailcmp() to compare s1[0] and s2[0]. strtailcmp() returns 0
if "a" and "b" or "a" and "ab", it's a wrong behavior. This patch
fixes it.

Signed-off-by: "Juha Leppanen" <juha_motorsportcom@luukku.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Juha Leppanen <juha_motorsportcom@luukku.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091207170040.19230.37464.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tools/perf/util/probe-finder.c

@@ -106,7 +106,7 @@ static int strtailcmp(const char *s1, const char *s2)
 {
 	int i1 = strlen(s1);
 	int i2 = strlen(s2);
-	while (--i1 > 0 && --i2 > 0) {
+	while (--i1 >= 0 && --i2 >= 0) {
 		if (s1[i1] != s2[i2])
 			return s1[i1] - s2[i2];
 	}