mmc: au1xmmc: Drop redundant code in au1xmmc_send_command()

The in-parameter "wait" is always set to 0 by the caller, hence just drop
it and its corresponding code.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Manuel Lauss <manuel.lauss@gmail.com>
Link: https://lore.kernel.org/r/20200406114337.8802-1-ulf.hansson@linaro.org