video: mxc: Avoid setting global_data fb_base

This is not used, so don't set it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/video/imx/mxc_ipuv3_fb.c b/drivers/video/imx/mxc_ipuv3_fb.c
index 039b220..fdeb3ca 100644
--- a/drivers/video/imx/mxc_ipuv3_fb.c
+++ b/drivers/video/imx/mxc_ipuv3_fb.c
@@ -403,7 +403,6 @@
 		(uint32_t) fbi->fix.smem_start, fbi->fix.smem_len);
 
 	fbi->screen_size = fbi->fix.smem_len;
-	gd->fb_base = fbi->fix.smem_start;
 
 	/* Clear the screen */
 	memset((char *)fbi->screen_base, 0, fbi->fix.smem_len);
@@ -633,7 +632,6 @@
 	mmu_set_region_dcache_behaviour(fb_start, fb_end - fb_start,
 					DCACHE_WRITEBACK);
 	video_set_flush_dcache(dev, true);
-	gd->fb_base = fb_start;
 
 	return 0;
 }