mm: convert anon_vma->lock to a mutex

mm: convert anon_vma->lock to a mutex

Straightforward conversion of anon_vma->lock to a mutex.

Signed-off-by: Peter Zijlstra <[email protected]>
Acked-by: Hugh Dickins <[email protected]>
Reviewed-by: KOSAKI Motohiro <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: David Miller <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Russell King <[email protected]>
Cc: Paul Mundt <[email protected]>
Cc: Jeff Dike <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Nick Piggin <[email protected]>
Cc: Namhyung Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>