mmc: dw_mmc: Fix null dma_ops access when use_dma is false

host->dma_ops is not valid if host->usa dma is 0 so protect
host->dma_ops reference in dw_mci_resume

Signed-off-by: Jonathan Kliegman <kliegs@chromium.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/dw_mmc.c

@@ -2186,7 +2186,7 @@ int dw_mci_resume(struct dw_mci *host)
 		return ret;
 	}
 
-	if (host->dma_ops->init)
+	if (host->use_dma && host->dma_ops->init)
 		host->dma_ops->init(host);
 
 	/* Restore the old value at FIFOTH register */