tools: Fix typo in ktest.pl

Correct spelling "faied" to "failed" in
tools/testing/ktest/ktest.pl
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

tools/testing/ktest/ktest.pl

@@ -2601,7 +2601,7 @@ sub config_bisect {
     # read directly what we want to check
     my %config_check;
     open (IN, $output_config)
-	or dodie "faied to open $output_config";
+	or dodie "failed to open $output_config";
 
     while (<IN>) {
 	if (/^((CONFIG\S*)=.*)/) {