Revert "mmc: sdhci: Remove unneeded quirk2 flag of O2 SD host controller"

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>

drivers/mmc/host/sdhci-pci-o2micro.c

@@ -432,7 +432,6 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
 					mmc_hostname(host->mmc));
 				host->flags &= ~SDHCI_SIGNALING_330;
 				host->flags |= SDHCI_SIGNALING_180;
-				host->quirks2 |= SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD;
 				host->mmc->caps2 |= MMC_CAP2_NO_SD;
 				host->mmc->caps2 |= MMC_CAP2_NO_SDIO;
 				pci_write_config_dword(chip->pdev,
@@ -682,6 +681,7 @@ static const struct sdhci_ops sdhci_pci_o2_ops = {
 const struct sdhci_pci_fixes sdhci_o2 = {
 	.probe = sdhci_pci_o2_probe,
 	.quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
+	.quirks2 = SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD,
 	.probe_slot = sdhci_pci_o2_probe_slot,
 #ifdef CONFIG_PM_SLEEP
 	.resume = sdhci_pci_o2_resume,