mmc: mmci: Remove redundant check of status for DATA irq

We don't need to verify the content of the status register twice, while
we are about to handle a DATA irq. Instead let's leave all verification
to be handled by mmci_data_irq().

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>