dm: imx: cm_fx6: Add MMC support for CONFIG_BLK

When CONFIG_BLK is enabled our weak board_mmc_init() will not be called.
Since there is no clock driver for MX6 yet, we must manually enable the
clocks.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/board/compulab/cm_fx6/cm_fx6.c b/board/compulab/cm_fx6/cm_fx6.c
index ecefe39..ff3bab7 100644
--- a/board/compulab/cm_fx6/cm_fx6.c
+++ b/board/compulab/cm_fx6/cm_fx6.c
@@ -678,6 +678,17 @@
 
 	cm_fx6_setup_display();
 
+	/* This should be done in the MMC driver when MX6 has a clock driver */
+#ifdef CONFIG_FSL_ESDHC
+	if (IS_ENABLED(CONFIG_BLK)) {
+		int i;
+
+		cm_fx6_set_usdhc_iomux();
+		for (i = 0; i < CONFIG_SYS_FSL_USDHC_NUM; i++)
+			enable_usdhc_clk(1, i);
+	}
+#endif
+
 	return 0;
 }