Revert "omap_hsmmc: update struct hsmmc to accommodate omap3 from DT"

This reverts commit 46831c1a.
This reserved area at the beginning of struct hsmm, will be used later to
support ADMA

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>