x86: Convert MMC to driver model

Convert the pci_mmc driver over to driver model and migrate all x86 boards
that use it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
[bmeng: remove DM_MMC from edison_defconfig]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/cpu/queensbay/Makefile b/arch/x86/cpu/queensbay/Makefile
index af3ffad..c068199 100644
--- a/arch/x86/cpu/queensbay/Makefile
+++ b/arch/x86/cpu/queensbay/Makefile
@@ -5,4 +5,4 @@
 #
 
 obj-y += fsp_configs.o irq.o
-obj-y += tnc.o topcliff.o
+obj-y += tnc.o