sdhci-of: rename main driver file prior to reorganization

This patch renames sdhci-of.c to sdhci-of-core.c before reorganizing the
driver to support additional hardware.

The driver is still built as sdhci-of despite the rename of the file.  No
functional change.
Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/mmc/host/Makefile

@@ -13,7 +13,6 @@ obj-$(CONFIG_MMC_MXC)		+= mxcmmc.o
 obj-$(CONFIG_MMC_SDHCI)		+= sdhci.o
 obj-$(CONFIG_MMC_SDHCI_PCI)	+= sdhci-pci.o
 obj-$(CONFIG_MMC_RICOH_MMC)	+= ricoh_mmc.o
-obj-$(CONFIG_MMC_SDHCI_OF)	+= sdhci-of.o
 obj-$(CONFIG_MMC_SDHCI_PLTFM)	+= sdhci-pltfm.o
 obj-$(CONFIG_MMC_SDHCI_S3C)	+= sdhci-s3c.o
 obj-$(CONFIG_MMC_WBSD)		+= wbsd.o
@@ -37,6 +36,9 @@ obj-$(CONFIG_MMC_CB710)	+= cb710-mmc.o
 obj-$(CONFIG_MMC_VIA_SDMMC)	+= via-sdmmc.o
 obj-$(CONFIG_SDH_BFIN)		+= bfin_sdh.o
 
+obj-$(CONFIG_MMC_SDHCI_OF)	+= sdhci-of.o
+sdhci-of-y				:= sdhci-of-core.o
+
 ifeq ($(CONFIG_CB710_DEBUG),y)
 	CFLAGS-cb710-mmc	+= -DDEBUG
 endif