[arch][arm64] Fix load/store excusive on Cortex-A53
[arch][arm64] Fix load/store excusive on Cortex-A53

Change outer mair value for normal memory from write-through to
write-back.

Change-Id: I1c6f662985b4350501be453571883ca5bdd357ce

skabet/lk,skabet/lk,minglun-tsai/lk,sndnvaps/lk,ErikCorryGoogle/lk,skabet/lk,ErikCorryGoogle/lk,littlekernel/lk,skabet/lk,nvll/lk,littlekernel/lk,travisg/lk,minglun-tsai/lk,nvll/lk,sndnvaps/lk,GCrean/lk,GCrean/lk,nvll/lk,littlekernel/lk,travisg/lk,travisg/lk,nvll/lk,nvll/lk,sndnvaps/lk,srodrig1/lk,skabet/lk,sndnvaps/lk,minglun-tsai/lk,GCrean/lk,hollanderic/lkstuff,hollanderic/lkstuff,srodrig1/lk,travisg/lk,sndnvaps/lk,GCrean/lk,littlekernel/lk,hollanderic/lkstuff,ErikCorryGoogle/lk,ErikCorryGoogle/lk,srodrig1/lk,hollanderic/lkstuff,srodrig1/lk,GCrean/lk,srodrig1/lk,minglun-tsai/lk