lowmemorykiller: Account for highmem during kswapd reclaim

Currently most memory reclaim is done through kswapd.
Since kswapd uses a gfp mask of GFP_KERNEL, and because
the lowmemorykiller is zone aware, the lowmemorykiller will
ignore highmem most of the time.
This results in the lowmemorykiller being overly aggressive.

The fix to this issue is to allow the lowmemorykiller to
count highmem when being called by the kswapd if the lowmem
watermarks are satisfied.

Bug: 17626969
Change-Id: I938644584f374763d10d429d835e74daa4854a38
Signed-off-by: Liam Mark <lmark@codeaurora.org>
Signed-off-by: Naveen Ramaraj <nramaraj@codeaurora.org>
mm: Increase number of GFP masks

The __GFP_CMA mask is now placed after all available GFP masks.
With this we need to increase the total number of GFP flags.
Do so accordingly.

Bug: 17626969
CRs-Fixed: 648978
Change-Id: I53f5f064ac16a50ee10c84ff2bb50fdb7e085bd0
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Naveen Ramaraj <nramaraj@codeaurora.org>