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/a4m2k_defconfig b/configs/a4m2k_defconfig
index 46180f5..e9510ff 100644
--- a/configs/a4m2k_defconfig
+++ b/configs/a4m2k_defconfig
@@ -24,5 +24,6 @@
 CONFIG_CMD_LINK_LOCAL=y
 CONFIG_CMD_CACHE=y
 CONFIG_CMD_UBI=y
+# CONFIG_PCI is not set
 CONFIG_LIB_RAND=y
 CONFIG_OF_LIBFDT=y