[ARM] 5529/1: davinci: MMC platform support: DMA_32BIT_MASK --> DMA_BIT_MASK(32)

Some DMA_32BIT_MASK usage snuck in with the MMC platform support.
Convert these to the new preferred DMA_BIT_MASK(32).

Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>