procfs: parse mount options

procfs: parse mount options

Add support for procfs mount options.  Actual mount options are coming in
the next patches.

Signed-off-by: Vasiliy Kulikov <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Greg KH <[email protected]>
Cc: Theodore Tso <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: James Morris <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>