mmc: host: omap_hsmmc: use mmc_host's vmmc and vqmmc

No functional change. Instead of using omap_hsmmc_host's vcc and vcc_aux
members, use vmmc and vqmmc present in mmc_host which is present
for the same purpose.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Reviewed-by: Roger Quadros <rogerq@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>