[v2][SRU Artful/Bionic][Patch 0/1] fix false positives in W+X checking

[Manoj Iyer]

Please consider this patch to Bionic, Artful. On
ARM64 system from Cavium and Qualcomm we see random false positive
warning messages wrt W+X checking. 
"arm64/mm: Found insecure W+X mapping at address 0000000000a99000/0xa99000" 
while booting.

This patch was cherry-picked cleanly on to bionic and artful, previously
I had the same patch cherry-picked from linux-next and tested that patch
on QTI and Cavium systems. I am resending this patch again as a
cherry-pick from linus tree.

I will submit a backport of this patch for xenial shortly.