mmc: core: Move public functions from card.h to private headers

A significant amount of functions and other definitions are available
through the public mmc card.h header file. Let's slim down this public mmc
interface, as to prevent users from abusing it, by moving some of the
functions/definitions to private mmc header files.

This change concentrates on moving the functions into private mmc headers,
following changes may continue with additional clean-ups.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index 8f5bf5f8..611f5c6 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -21,6 +21,7 @@
 #include "queue.h"
 #include "block.h"
 #include "core.h"
+#include "card.h"
 
 #define MMC_QUEUE_BOUNCESZ	65536