mmc: cmdq: configure task descriptor list base register on enable

When enabling cmdq mode for the first time, need to allocate descriptors
table. After controller reset and enabling cmdq next time, still need to
update CQTDLBA and CQTDLBAU registers with already allocated descriptors
table (desc_dma_base).

Change-Id: Ide89eebbce5a193cd44a1ea4ec65403f98e2a7ab
Signed-off-by: Konstantin Dorfman <kdorfman@codeaurora.org>