trace-graph: Have status marker times with white background
trace-graph: Have status marker times with white background

It's hard to see the times in the status bar if everything has
a grey background. Make the times have a white background, it
makes it easier to see.

Signed-off-by: Steven Rostedt <43232e92d70cc7aa53504ad0397085ee47bad87f@goodmis.org>

bigzz/trace-cmd,bigzz/trace-cmd