mmc: sdhci-pci: enable runtime pm for Intel Merrifield platform

Enable runtime pm support on Intel Merrifield platform.

Signed-off-by: Yunpeng Gao <yunpeng.gao@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index cfe8a2c..ff9ab62 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -318,6 +318,7 @@
 static const struct sdhci_pci_fixes sdhci_intel_mrfl_mmc = {
 	.quirks		= SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
 	.quirks2	= SDHCI_QUIRK2_BROKEN_HS200,
+	.allow_runtime_pm = true,
 	.probe_slot	= intel_mrfl_mmc_probe_slot,
 };