tridentfb: add imageblit acceleration for Blade3D family

Add imageblit acceleration for the Blade3D family of cores.  The code is
based on code from the cyblafb driver.

It is a step toward assimilating back the cyblafb driver into the
tridentfb driver.  The cyblafb driver handles a subfamily of the Trident
Blade3d cores.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/video/trident.h b/include/video/trident.h
index 85ced9d..b6ce19d 100644
--- a/include/video/trident.h
+++ b/include/video/trident.h
@@ -135,6 +135,7 @@
 #define CMD	0x2144
 #define ROP	0x2148
 #define COLOR	0x2160
+#define BGCOLOR	0x2164
 #define SRC1	0x2100
 #define SRC2	0x2104
 #define DST1	0x2108