ext4: fix kconfig typo and extra whitespace

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/Kconfig

@@ -170,7 +170,7 @@ config EXT4DEV_COMPAT
 	help
 	  Starting with 2.6.28, the name of the ext4 filesystem was
 	  renamed from ext4dev to ext4.  Unfortunately there are some
-	  lagecy userspace programs (such as klibc's fstype) have
+	  legacy userspace programs (such as klibc's fstype) have
 	  "ext4dev" hardcoded.
 
 	  To enable backwards compatibility so that systems that are