mm: make counts of CMA free pages correct

Both patches needed, second patch (among other things) fixes
a bug in the first.

commit 2139cbe627b8910ded55148f87ee10f7485408ed
Author: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Date:   Mon Oct 8 16:32:00 2012 -0700

    cma: fix counting of isolated pages

    Isolated free pages shouldn't be accounted to NR_FREE_PAGES counter.  Fix
    it by properly decreasing/increasing NR_FREE_PAGES counter in
    set_migratetype_isolate()/unset_migratetype_isolate() and removing counter
    adjustment for isolated pages from free_one_page() and split_free_page().

    Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
    Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
    Cc: Marek Szyprowski <m.szyprowski@samsung.com>
    Cc: Michal Nazarewicz <mina86@mina86.com>
    Cc: Minchan Kim <minchan@kernel.org>
    Cc: Mel Gorman <mgorman@suse.de>
    Cc: Hugh Dickins <hughd@google.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    [lbassel@codeaurora.org: backport from 3.7, small changes needed]
    Signed-off-by: Larry Bassel <lbassel@codeaurora.org>

commit d1ce749a0db12202b711d1aba1d29e823034648d
Author: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Date:   Mon Oct 8 16:32:02 2012 -0700

    cma: count free CMA pages

    Add NR_FREE_CMA_PAGES counter to be later used for checking watermark in
    __zone_watermark_ok().  For simplicity and to avoid #ifdef hell make this
    counter always available (not only when CONFIG_CMA=y).

    [akpm@linux-foundation.org: use conventional migratetype naming]
    Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
    Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
    Cc: Marek Szyprowski <m.szyprowski@samsung.com>
    Cc: Michal Nazarewicz <mina86@mina86.com>
    Cc: Minchan Kim <minchan@kernel.org>
    Cc: Mel Gorman <mgorman@suse.de>
    Cc: Hugh Dickins <hughd@google.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    [lbassel@codeaurora.org: backport from 3.7, small changes needed]
    Signed-off-by: Larry Bassel <lbassel@codeaurora.org>

Change-Id: I7d4f5fe0b6931192706337e0b730f43e7cccd031
Signed-off-by: Larry Bassel <lbassel@codeaurora.org>
Signed-off-by: Neha Pandey <nehap@codeaurora.org>