mmc: bfin_sdh: drop redundant MMC depend string

The host/Kconfig file is only included when MMC is selected.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>