selftests/ftrace: Add color to the PASS / FAIL results

Now that ftracetest has over 80 tests, it is difficult to simply scroll
up the console window to find the failed tests when it reports just two
tests have failed. In order to make this stand out better, have the
color of the word "PASS" be green, "FAIL" and "XFAIL" be red, and all
other results be blue. This helps tremendously in quickly spotting the
failed tests by just scrolling up the console window.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>