selftest/ftrace: Fix typo in trigger-snapshot.tc

This patch fixes a spelling typo in trigger-snapshot.tc

[skhan@linuxfoundation.org: Fix typo in commit log]
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Acked-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: NShuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/ftrace/test.d/trigger/trigger-snapshot.tc

@@ -28,7 +28,7 @@ if [ -z "$FEATURE" ]; then
     exit_unsupported
 fi
 
-echo "Test snapshot tigger"
+echo "Test snapshot trigger"
 echo 0 > snapshot
 echo 1 > events/sched/sched_process_fork/enable
 ( echo "forked")