fs/Kconfig: move configfs out

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
diff --git a/fs/Kconfig b/fs/Kconfig
index e9103b9..d7d7f1b 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -182,17 +182,7 @@
 config HUGETLB_PAGE
 	def_bool HUGETLBFS
 
-config CONFIGFS_FS
-	tristate "Userspace-driven configuration filesystem"
-	depends on SYSFS
-	help
-	  configfs is a ram-based filesystem that provides the converse
-	  of sysfs's functionality. Where sysfs is a filesystem-based
-	  view of kernel objects, configfs is a filesystem-based manager
-	  of kernel objects, or config_items.
-
-	  Both sysfs and configfs can and should exist together on the
-	  same system. One is not a replacement for the other.
+source "fs/configfs/Kconfig"
 
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