mmc: Migrate MMC_SUPPORTS_TUNING to Kconfig

The constraints on the MMC_SUPPORTS_TUNING symbol can easily be
expressed in Kconfig (with the addition of SPL_MMC_SUPPORTS_TUNING).
Furthermore, in order to remove <common.h> from the MMC subsystem, the
way this symbol is used today needs to be changed in order to continue
functioning.

Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c
index 595d88b..5ac1c6a 100644
--- a/drivers/mmc/fsl_esdhc.c
+++ b/drivers/mmc/fsl_esdhc.c
@@ -1102,7 +1102,7 @@
 	return esdhc_init_common(priv, &plat->mmc);
 }
 
-#ifdef MMC_SUPPORTS_TUNING
+#if CONFIG_IS_ENABLED(MMC_SUPPORTS_TUNING)
 static int fsl_esdhc_execute_tuning(struct udevice *dev, uint32_t opcode)
 {
 	struct fsl_esdhc_plat *plat = dev_get_plat(dev);
@@ -1175,7 +1175,7 @@
 	.get_cd		= fsl_esdhc_get_cd,
 	.send_cmd	= fsl_esdhc_send_cmd,
 	.set_ios	= fsl_esdhc_set_ios,
-#ifdef MMC_SUPPORTS_TUNING
+#if CONFIG_IS_ENABLED(MMC_SUPPORTS_TUNING)
 	.execute_tuning = fsl_esdhc_execute_tuning,
 #endif
 	.reinit = fsl_esdhc_reinit,