Underscores previously caused the next character in the label to be
printed using subscript due to the enhanced string support in gnuplot.
(From OE-Core rev: a8039d601187b28d9cec4402c9e0bd72b2805eb2)
Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
(cherry picked from commit 282b48f90f77e0766993018d22fe03dd303febdc)
Signed-off-by: Steve Sakoman <steve@sakoman.com>