video: vt8500lcdfb: Remove kfree call since devm_kzalloc() is used

We use devm_kzalloc() to allocate memory for the struct vt8500lcd_info
pointer fbi, so there is no need to free it in vt8500lcd_remove().

Signed-off-by: Emil Goode <emilgoode@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>