MIPS: Alchemy: remove all CONFIG_SOC_AU1??? defines

Now that no driver any longer depends on the CONFIG_SOC_AU1???  symbols,
it's time to get rid of them: Move some of the platform devices to the
boards which can use them, Rename a few (unused) constants in the header,
Replace them with MIPS_ALCHEMY in the various Kconfig files.  Finally
delete them altogether from the Alchemy Kconfig file.

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/2707/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 8c87096..6d74f49 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -263,7 +263,7 @@
 
 config MMC_AU1X
 	tristate "Alchemy AU1XX0 MMC Card Interface support"
-	depends on SOC_AU1200
+	depends on MIPS_ALCHEMY
 	help
 	  This selects the AMD Alchemy(R) Multimedia card interface.
 	  If you have a Alchemy platform with a MMC slot, say Y or M here.