Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

Documentation/filesystems/vfs.txt

@@ -97,7 +97,7 @@ functions:
 The passed struct file_system_type describes your filesystem. When a
 request is made to mount a filesystem onto a directory in your namespace,
 the VFS will call the appropriate mount() method for the specific
-filesystem.  New vfsmount refering to the tree returned by ->mount()
+filesystem.  New vfsmount referring to the tree returned by ->mount()
 will be attached to the mountpoint, so that when pathname resolution
 reaches the mountpoint it will jump into the root of that vfsmount.