mm: cleancache: s/flush/invalidate/

Per akpm suggestions alter the use of the term flush to be
invalidate. The next patch will do this across all MM.

This change is completely cosmetic.

[v9: [email protected]: change "flush" to "invalidate", part 3]

Signed-off-by: Dan Magenheimer <[email protected]>
Cc: Kamezawa Hiroyuki <[email protected]>
Cc: Jan Beulich <[email protected]>
Reviewed-by: Seth Jennings <[email protected]>
Cc: Jeremy Fitzhardinge <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Nitin Gupta <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Chris Mason <[email protected]>
Cc: Rik Riel <[email protected]>
Cc: Andrew Morton <[email protected]>
[v10: Fixed  fs: move code out of buffer.c conflict change]
Signed-off-by: Konrad Rzeszutek Wilk <[email protected]>
7 files changed