linux-imx

fbdev: vfb: add description to module parameters

Add description to "videomemorysize" and "vfb_enable" module parameters to
make them a bit friendly to the end user.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>