tridentfb: remove misplaced enable_mmio()

Remove redundant enable_mmio() call as the mmio mode is enabled in the probe
function earlier.

Signed-off-by: Krzysztof Helt <[e-mail]>
Cc: "Antonino A. Daplas" <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/video/tridentfb.c

···
 	vblankstart = var->yres;
 	vblankend = vtotal + 2;
 
-	enable_mmio();
 	crtc_unlock();
 	write3CE(CyberControl, 8);