drivers/pci/Kconfig: Add PCI

Add 'PCI' as a menu option and migrate all existing users.

Signed-off-by: Tom Rini <trini@konsulko.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
diff --git a/configs/canmb_defconfig b/configs/canmb_defconfig
index f1e3265..ae8e040 100644
--- a/configs/canmb_defconfig
+++ b/configs/canmb_defconfig
@@ -7,3 +7,4 @@
 CONFIG_CMD_DHCP=y
 CONFIG_CMD_MII=y
 CONFIG_CMD_SNTP=y
+# CONFIG_PCI is not set