omap: zoom: wl1271 slot is MMC_CAP_POWER_OFF_CARD

This patch complements ed919b01 "mmc: sdio: fix runtime PM anomalies by
introducing MMC_CAP_POWER_OFF_CARD" by declaring MMC_CAP_POWER_OFF_CARD
on the ZOOM's wl1271 mmc slot.

This is required in order not to break runtime PM support for the wl1271
sdio driver.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>