Clarify that UNW_IA64_PR works like the "move predicates" instruction, i.e., it acesses the physical (unrotated) contents of p16-p63.
Clarify that UNW_IA64_PR works like the "move predicates" instruction, i.e.,
it acesses the physical (unrotated) contents of p16-p63.

(Logical change 1.292)

dropbox/libunwind,CyanogenMod/android_external_libunwind,tkelman/libunwind,vegard/libunwind,pathscale/libunwind,rntz/libunwind,wdv4758h/libunwind,zliu2014/libunwind-tilegx,unkadoug/libunwind,wdv4758h/libunwind,adsharma/libunwind,0xlab/0xdroid-external_libunwind,ehsan/libunwind,zliu2014/libunwind-tilegx,libunwind/libunwind,rogwfu/libunwind,pathscale/libunwind,DroidSim/platform_external_libunwind,frida/libunwind,Chilledheart/libunwind,unkadoug/libunwind,androidarmv6/android_external_libunwind,dropbox/libunwind,Chilledheart/libunwind,atanasyan/libunwind,evaautomation/libunwind,dreal-deps/libunwind,maltek/platform_external_libunwind,pathscale/libunwind,tkelman/libunwind,zeldin/platform_external_libunwind,djwatson/libunwind,fdoray/libunwind,martyone/libunwind,mpercy/libunwind,rntz/libunwind,project-zerus/libunwind,jrmuizel/libunwind,tony/libunwind,zeldin/platform_external_libunwind,Keno/libunwind,fdoray/libunwind,lat/libunwind,cloudius-systems/libunwind,igprof/libunwind,androidarmv6/android_external_libunwind,dagar/libunwind,mpercy/libunwind,joyent/libunwind,cloudius-systems/libunwind,igprof/libunwind,frida/libunwind,igprof/libunwind,atanasyan/libunwind-android,martyone/libunwind,geekboxzone/lollipop_external_libunwind,joyent/libunwind,djwatson/libunwind,atanasyan/libunwind,CyanogenMod/android_external_libunwind,CyanogenMod/android_external_libunwind,rntz/libunwind,martyone/libunwind,olibc/libunwind,dagar/libunwind,adsharma/libunwind,Keno/libunwind,bo-on-software/libunwind,bo-on-software/libunwind,rantala/libunwind,dropbox/libunwind,evaautomation/libunwind,rantala/libunwind,jrmuizel/libunwind,tkelman/libunwind,rogwfu/libunwind,krytarowski/libunwind,geekboxzone/mmallow_external_libunwind,dagar/libunwind,tronical/libunwind,atanasyan/libunwind-android,libunwind/libunwind,Chilledheart/libunwind,geekboxzone/lollipop_external_libunwind,tony/libunwind,jrmuizel/libunwind,zliu2014/libunwind-tilegx,fdoray/libunwind,android-ia/platform_external_libunwind,DroidSim/platform_external_libunwind,zeldin/platform_external_libunwind,Keno/libunwind,fillexen/libunwind,cms-externals/libunwind,android-ia/platform_external_libunwind,maltek/platform_external_libunwind,project-zerus/libunwind,rantala/libunwind,DroidSim/platform_external_libunwind,rogwfu/libunwind,olibc/libunwind,yuyichao/libunwind,vtjnash/libunwind,unkadoug/libunwind,tronical/libunwind,androidarmv6/android_external_libunwind,lat/libunwind,fillexen/libunwind,ehsan/libunwind,dreal-deps/libunwind,krytarowski/libunwind,vegard/libunwind,krytarowski/libunwind,geekboxzone/lollipop_external_libunwind,yuyichao/libunwind,adsharma/libunwind,bo-on-software/libunwind,frida/libunwind,joyent/libunwind,yuyichao/libunwind,vtjnash/libunwind,project-zerus/libunwind,atanasyan/libunwind-android,cms-externals/libunwind,maltek/platform_external_libunwind,tony/libunwind,olibc/libunwind,evaautomation/libunwind,0xlab/0xdroid-external_libunwind,SyndicateRogue/libunwind,dreal-deps/libunwind,fillexen/libunwind,libunwind/libunwind,atanasyan/libunwind,geekboxzone/mmallow_external_libunwind,SyndicateRogue/libunwind,ehsan/libunwind,vtjnash/libunwind,vegard/libunwind,djwatson/libunwind,geekboxzone/mmallow_external_libunwind,cms-externals/libunwind,cloudius-systems/libunwind,mpercy/libunwind,SyndicateRogue/libunwind,0xlab/0xdroid-external_libunwind,wdv4758h/libunwind,android-ia/platform_external_libunwind,tronical/libunwind,lat/libunwind