[PATCH] mmc: fix MMIO vs memory races in sdhci

Sprinkle some mmiowb() where needed (writeX() before unlock()).

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>