vesafb occassionally gets the size wrong when setting the mtrr.  When X or DRI
attempts to set the mtrr, it will fail due to range overlap significantly
affecting their performance.  Disable mtrr and let the user explicitly enable
it with the mtrr:n option.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>