mmc: kconfig: replace PPC_OF with PPC

The PPC_OF is a ppc specific option which is used to mean that the
firmware device tree access functions are available. Since all the
ppc platforms have a device tree, it is aways set to 'y' for ppc.
So it makes no sense to keep a such option in the current kernel.
Replace it with PPC.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/Kconfig

@@ -132,7 +132,7 @@ config MMC_SDHCI_OF_ARASAN
 config MMC_SDHCI_OF_ESDHC
 	tristate "SDHCI OF support for the Freescale eSDHC controller"
 	depends on MMC_SDHCI_PLTFM
-	depends on PPC_OF
+	depends on PPC
 	select MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER
 	help
 	  This selects the Freescale eSDHC controller support.
@@ -144,7 +144,7 @@ config MMC_SDHCI_OF_ESDHC
 config MMC_SDHCI_OF_HLWD
 	tristate "SDHCI OF support for the Nintendo Wii SDHCI controllers"
 	depends on MMC_SDHCI_PLTFM
-	depends on PPC_OF
+	depends on PPC
 	select MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER
 	help
 	  This selects the Secure Digital Host Controller Interface (SDHCI)