mmc: Remove ops from struct mmc and put in mmc_ops

Remove the in-structure ops and put them in mmc_ops with
a constant pointer to it.

This makes the mmc structure smaller as well as conserving
code space (in theory).

All in-tree drivers are converted as well; this is done in a
single patch in order to not break git bisect.

Changes since V1:
Fix compilation b0rked issue on omap platforms where OMAP_GPIO was
not set.

Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com>
diff --git a/drivers/mmc/mxsmmc.c b/drivers/mmc/mxsmmc.c
index 245f9d0..97c9ee8 100644
--- a/drivers/mmc/mxsmmc.c
+++ b/drivers/mmc/mxsmmc.c
@@ -363,6 +363,12 @@
 	return 0;
 }
 
+static const struct mmc_ops mxsmmc_ops = {
+	.send_cmd	= mxsmmc_send_cmd,
+	.set_ios	= mxsmmc_set_ios,
+	.init		= mxsmmc_init,
+};
+
 int mxsmmc_initialize(bd_t *bis, int id, int (*wp)(int), int (*cd)(int))
 {
 	struct mmc *mmc = NULL;
@@ -400,11 +406,7 @@
 	priv->regs = mxs_ssp_regs_by_bus(id);
 
 	sprintf(mmc->name, "MXS MMC");
-	mmc->send_cmd = mxsmmc_send_cmd;
-	mmc->set_ios = mxsmmc_set_ios;
-	mmc->init = mxsmmc_init;
-	mmc->getcd = NULL;
-	mmc->getwp = NULL;
+	mmc->ops = &mxsmmc_ops;
 	mmc->priv = priv;
 
 	mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;