dt-binding: display: Require two resets on mantix panel

We need to reset both for the panel to show an image.

Signed-off-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/15d3dc7eb4e031f380be1298ed3ac9085626f26b.1602584953.git.agx@sigxcpu.org