fs/Kconfig: move nilfs2 out

fs/Kconfig file was split into individual fs/*/Kconfig files before
nilfs was merged.  I've found the current config entry of nilfs is
tainting the work.  Sorry, I didn't notice.  This fixes the violation.
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Alexey Dobriyan <adobriyan@gmail.com>

fs/Kconfig

@@ -186,32 +186,7 @@ source "fs/romfs/Kconfig"
 source "fs/sysv/Kconfig"
 source "fs/ufs/Kconfig"
 source "fs/exofs/Kconfig"
-
-config NILFS2_FS
-	tristate "NILFS2 file system support (EXPERIMENTAL)"
-	depends on BLOCK && EXPERIMENTAL
-	select CRC32
-	help
-	  NILFS2 is a log-structured file system (LFS) supporting continuous
-	  snapshotting.  In addition to versioning capability of the entire
-	  file system, users can even restore files mistakenly overwritten or
-	  destroyed just a few seconds ago.  Since this file system can keep
-	  consistency like conventional LFS, it achieves quick recovery after
-	  system crashes.
-
-	  NILFS2 creates a number of checkpoints every few seconds or per
-	  synchronous write basis (unless there is no change).  Users can
-	  select significant versions among continuously created checkpoints,
-	  and can change them into snapshots which will be preserved for long
-	  periods until they are changed back to checkpoints.  Each
-	  snapshot is mountable as a read-only file system concurrently with
-	  its writable mount, and this feature is convenient for online backup.
-
-	  Some features including atime, extended attributes, and POSIX ACLs,
-	  are not supported yet.
-
-	  To compile this file system support as a module, choose M here: the
-	  module will be called nilfs2.  If unsure, say N.
+source "fs/nilfs2/Kconfig"
 
 endif # MISC_FILESYSTEMS
 

fs/nilfs2/Kconfig

+config NILFS2_FS
+	tristate "NILFS2 file system support (EXPERIMENTAL)"
+	depends on BLOCK && EXPERIMENTAL
+	select CRC32
+	help
+	  NILFS2 is a log-structured file system (LFS) supporting continuous
+	  snapshotting.  In addition to versioning capability of the entire
+	  file system, users can even restore files mistakenly overwritten or
+	  destroyed just a few seconds ago.  Since this file system can keep
+	  consistency like conventional LFS, it achieves quick recovery after
+	  system crashes.
+
+	  NILFS2 creates a number of checkpoints every few seconds or per
+	  synchronous write basis (unless there is no change).  Users can
+	  select significant versions among continuously created checkpoints,
+	  and can change them into snapshots which will be preserved for long
+	  periods until they are changed back to checkpoints.  Each
+	  snapshot is mountable as a read-only file system concurrently with
+	  its writable mount, and this feature is convenient for online backup.
+
+	  Some features including atime, extended attributes, and POSIX ACLs,
+	  are not supported yet.
+
+	  To compile this file system support as a module, choose M here: the
+	  module will be called nilfs2.  If unsure, say N.