[PATCH] matroxfb: simply return what i2c_add_driver() does

insmod will tell us when the module failed to load.  We do no further
processing on the return from i2c_add_driver(), so just return what
i2c_add_driver() did, instead of storing it.

Add __init/__exit annotations while we're at it.

Signed-off-by: Arthur Othieno <apgo@patchbomb.org>
Acked-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>