tcx: use standard fields for framebuffer physical address and length

Use standard fields fbinfo.fix.smem_start and fbinfo.fix.smem_len for
physical address and length of framebuffer.

This also fixes output of the 'fbset -i' command - address and length of
the framebuffer are displayed correctly.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>