tridentfb: replace macros with functions

This patch replaces macros with static functions and puts tridentfb_par
pointer as the first argument of these functions.  These is a step toward
multihead support.

Additionally, bogus TRIDENT_MMIO define is removed as the driver supports
graphics cards only through the mmio mode.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>