[PATCH] staging: fbtft: force cast to non-__iomem pointer

[Garret Kelly]

> Can't we fix this properly, to use the correct type of pointer instead
> for non-__iomem allocations?

You mean making an alternate screen_base pointer inside fb_info that
isn't __iomem?  There are already a bunch of framebuffer drivers that
(ab)use screen_base to store non-__iomem pointers, so this didn't
strike me as too far out of line.

Garret