x86: conditionalize code for ARM neon optimization
x86: conditionalize code for ARM neon optimization

Conditionalize code for ARM neon optimizations so that other architectures
compile correctly.

Change-Id: I538b937734f3e6a3b318e40fcc45579bfa899f28

byterom/android_external_skia,sombree/android_external_skia,InfinitiveOS/external_skia,byterom/android_external_skia,Khaon/android_external_skia,HealthyHoney/temasek_SKIA,Khaon/android_external_skia,Khaon/android_external_skia,MinimalOS/android_external_skia,fire855/android_external_skia,Tesla-Redux/android_external_skia,Khaon/android_external_skia,temasek/android_external_skia,ench0/external_skia,byterom/android_external_skia,Khaon/android_external_skia,GladeRom/android_external_skia,temasek/android_external_skia,temasek/android_external_skia,NamelessRom/android_external_skia,MinimalOS/android_external_skia,HealthyHoney/temasek_SKIA,F-AOSP/platform_external_skia,temasek/android_external_skia,RadonX-ROM/external_skia,fire855/android_external_skia,fire855/android_external_skia,ench0/external_skia,F-AOSP/platform_external_skia,HealthyHoney/temasek_SKIA,Tesla-Redux/android_external_skia,sombree/android_external_skia,Tesla-Redux/android_external_skia,RadonX-ROM/external_skia,MinimalOS/android_external_skia,MinimalOS/external_skia,F-AOSP/platform_external_skia,Tesla-Redux/android_external_skia,TeslaOS/android_external_skia,RadonX-ROM/external_skia,temasek/android_external_skia,GladeRom/android_external_skia,TeslaOS/android_external_skia,GladeRom/android_external_skia,NamelessRom/android_external_skia,ench0/external_skia,Tesla-Redux/android_external_skia,InfinitiveOS/external_skia,fire855/android_external_skia,InfinitiveOS/external_skia,TeslaOS/android_external_skia,MinimalOS/android_external_skia,TeslaOS/android_external_skia,RadonX-ROM/external_skia,sombree/android_external_skia,RadonX-ROM/external_skia,RadonX-ROM/external_skia,sombree/android_external_skia,Tesla-Redux/android_external_skia,temasek/android_external_skia,GladeRom/android_external_skia,Khaon/android_external_skia,F-AOSP/platform_external_skia,ench0/external_skia,F-AOSP/platform_external_skia,fire855/android_external_skia,ench0/external_skia,InfinitiveOS/external_skia,MinimalOS/android_external_skia,MinimalOS/external_skia,MinimalOS/android_external_skia,F-AOSP/platform_external_skia,RadonX-ROM/external_skia,byterom/android_external_skia,NamelessRom/android_external_skia,TeslaOS/android_external_skia,HealthyHoney/temasek_SKIA,MinimalOS/external_skia,ench0/external_skia,MinimalOS/external_skia,HealthyHoney/temasek_SKIA,NamelessRom/android_external_skia,InfinitiveOS/external_skia,temasek/android_external_skia,ench0/external_skia,Khaon/android_external_skia,sombree/android_external_skia,MinimalOS/external_skia,NamelessRom/android_external_skia,GladeRom/android_external_skia,Khaon/android_external_skia,TeslaOS/android_external_skia,MinimalOS/android_external_skia,NamelessRom/android_external_skia,byterom/android_external_skia,fire855/android_external_skia,fire855/android_external_skia,sombree/android_external_skia,NamelessRom/android_external_skia,MinimalOS/external_skia,RadonX-ROM/external_skia,TeslaOS/android_external_skia,fire855/android_external_skia,byterom/android_external_skia,HealthyHoney/temasek_SKIA,byterom/android_external_skia,F-AOSP/platform_external_skia,sombree/android_external_skia,MinimalOS/external_skia,F-AOSP/platform_external_skia,InfinitiveOS/external_skia,MinimalOS/android_external_skia,Tesla-Redux/android_external_skia,Tesla-Redux/android_external_skia,InfinitiveOS/external_skia,sombree/android_external_skia,NamelessRom/android_external_skia,ench0/external_skia,InfinitiveOS/external_skia,byterom/android_external_skia,temasek/android_external_skia,MinimalOS/external_skia,TeslaOS/android_external_skia,HealthyHoney/temasek_SKIA,GladeRom/android_external_skia,HealthyHoney/temasek_SKIA,GladeRom/android_external_skia,GladeRom/android_external_skia