[ARM] omap: fix a pile of issues

This patch fixes a number of sillies, from missing 'const' to using
'return' in void functions, to functions with no arguments not even
'void' and a cast which isn't required.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/video/omap/omapfb_main.c b/drivers/video/omap/omapfb_main.c
index 5a5e407..1a49519 100644
--- a/drivers/video/omap/omapfb_main.c
+++ b/drivers/video/omap/omapfb_main.c
@@ -392,7 +392,7 @@
 	int bpp;
 
 	rg = &plane->fbdev->mem_desc.region[plane->idx];
-	fbi->screen_base	= (char __iomem *)rg->vaddr;
+	fbi->screen_base	= rg->vaddr;
 	fix->smem_start		= rg->paddr;
 	fix->smem_len		= rg->size;