mmc: sdhci-msm: Provide module/cmdline parameter for disabling cmdq

This provides module/cmdline parameter for disabling cmdq.
This may be required sometimes for testing cmdq v/s non-cmdq
mode for performance or other stability testing.
Pass cmdline parameter as (sdhci-msm.nocmdq=1) for disabling
cmdq via cmdline.

Change-Id: Ic0993a58d79f9c9b92daa7a581a5bce9ea24ed03
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>