mmc: cmdq-hci: Change unnecessary pr_err logs to pr_debug

Now that CMDQ device and driver are stable, Change unnecessary
pr_err logs to pr_debug.
Also use %pK instead of %p while printing addresses to avoid leaking
of kernel addresses.

Change-Id: I95683ffe0410daef86dd9a376f5769d8f40ae990
Signed-off-by: Vijay Viswanath <vviswana@codeaurora.org>