This reverts commit 414126f9.

This commit broke eMMC storage access on a new consumer MiniPC based on
AMD SoC, which has eMMC connected to:

02:00.0 SD Host controller: O2 Micro, Inc. Device 8620 (rev 01) (prog-if 01)
	Subsystem: O2 Micro, Inc. Device 0002

During probe, several errors are seen including:

  mmc1: Got data interrupt 0x02000000 even though no data operation was in progress.
  mmc1: Timeout waiting for hardware interrupt.
  mmc1: error -110 whilst initialising MMC card

Reverting this commit allows the eMMC storage to be detected & usable
again.
Signed-off-by: Daniel Drake <drake@endlessm.com>
Fixes: 414126f9 ("mmc: sdhci: Remove unneeded quirk2 flag of O2 SD host
controller")
Cc: stable@vger.kernel.org # v5.1+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>