This rename is done so that the driver matches the name of the
display controller and in preparation for adding support for more
panels to the driver.

This is just a basic file rename, with no code changes.
Signed-off-by: NOndrej Jirman <megous@megous.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Tested-by: NGuido Günther <agx@sigxcpu.org>
Reviewed-by: NGuido Günther <agx@sigxcpu.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200701162928.1638874-5-megous@megous.com