kernel-shark: Avoid the unnecessary calls of KsGLWidget::loadColors()

The tables of colors used by the OpenGL widget have to be updated
only when we load a new trace data file.

Link: http://lore.kernel.org/linux-trace-devel/20190314151012.905-10-ykaradzhov@vmware.com

Signed-off-by: Yordan Karadzhov <ykaradzhov@vmware.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
1 file changed