aboot: Update to choose between 4.4.0 or 4.4.3 toolchain based on environment
aboot: Update to choose between 4.4.0 or 4.4.3 toolchain based on environment

Change-Id: I0b56bd8336dbe4a470c202f5587517f2275d0b49

Blefish/android_bootable_bootloader_lk,xndcn/moboot-for-veer,chirayudesai/android_bootable_bootloader_lk,jsr-d10/android_bootable_bootloader_lk,MiCode/mi2_lk,t2m-foxfone/kernel_lk,Redmi-dev/android_bootable_lk,DooMLoRD/android_bootable_bootloader_lk,detule/lk-g2-spr,t2m-foxfone/kernel_lk,my4ndr0id/android_bootable_bootloader_lk,efidroid/lk,thornbirdblue/codeaurora_lk,M1cha/mi2_lk,t2m-foxfone/kernel_lk,zhuotong/mi2_lk_NoEmmc,idor/dk50-bootable_bootloader_lk,hanjae/lumiab0,utilite2/lk,lg-devs/g2-bootloader,xndcn/moboot-for-veer,Foxda-Tech/argo8-bootable-bootloader-lk,jsr-d9/android_kernel_lk,thornbirdblue/codeaurora_lk,jcsullins/moboot,pichina/lk,hanjae/lumiab0,DooMLoRD/android_bootable_bootloader_lk,Blefish/android_bootable_bootloader_lk,mozilla-b2g/kernel_lk,RonGokhale/android_lk_bootloader,Foxda-Tech/polaris-bootable-bootloader-lk,oubeichen/lk-v500,utilite2/lk,oubeichen/lk-v500,M1cha/android_bootable_bootloader_lk,lg-devs/g2-bootloader,beidl/lk_umia,utilite2/lk,RonGokhale/android_lk_bootloader,xndcn/moboot-for-veer,mozilla-b2g/kernel_lk,efidroid/lk,M1cha/android_bootable_bootloader_lk,M1cha/android_bootable_bootloader_lk,zhuotong/mi2_lk_NoEmmc,Redmi-dev/android_bootable_lk,jbott/lk_gee,jcsullins/moboot,pichina/lk,Foxda-Tech/polaris-bootable-bootloader-lk,t2m-foxfone/android_kernel_lk,oubeichen/lk-v500,thornbirdblue/codeaurora_lk,CanarySolutions/little-kernel,CanarySolutions/little-kernel,zhuotong/mi2_lk_NoEmmc,detule/lk-g2-spr,oubeichen/lk-v500,idor/dk50-bootable_bootloader_lk,M1cha/android_bootable_bootloader_lk,Foxda-Tech/argo8-bootable-bootloader-lk,Blefish/android_bootable_bootloader_lk,jsr-d9/android_kernel_lk,jsr-d10/android_bootable_bootloader_lk,mozilla-b2g/kernel_lk,Foxda-Tech/polaris-bootable-bootloader-lk,M1cha/mi2_lk,mozilla-b2g/fairphone2_kernel_lk,M1cha/mi2_lk,M1cha/lktris,jbott/lk_gee,zhuotong/mi2_lk_NoEmmc,Blefish/android_bootable_bootloader_lk,my4ndr0id/android_bootable_bootloader_lk,jsr-d9/android_kernel_lk,RonGokhale/android_lk_bootloader,xndcn/moboot-for-veer,mozilla-b2g/kernel_lk,jsr-d10/android_bootable_bootloader_lk,t2m-foxfone/android_kernel_lk,t2m-foxfone/kernel_lk,MiCode/mi2_lk,M1cha/lktris,t2m-foxfone/android_kernel_lk,Redmi-dev/android_bootable_lk,RonGokhale/android_lk_bootloader,beidl/lk_umia,my4ndr0id/android_bootable_bootloader_lk,thornbirdblue/codeaurora_lk,mozilla-b2g/kernel_lk,M1cha/android_bootable_bootloader_lk,idor/dk50-bootable_bootloader_lk,lg-devs/g2-bootloader,chirayudesai/android_bootable_bootloader_lk,Foxda-Tech/polaris-bootable-bootloader-lk,MiCode/mi2_lk,Foxda-Tech/argo8-bootable-bootloader-lk,M1cha/android_bootable_bootloader_lk,my4ndr0id/android_bootable_bootloader_lk,jsr-d10/android_bootable_bootloader_lk,M1cha/mi2_lk,beidl/lk_umia,pichina/lk,pichina/lk,MiCode/mi2_lk,jsr-d9/android_kernel_lk,jsr-d10/android_bootable_bootloader_lk,detule/lk-g2-spr,utilite2/lk,beidl/lk_umia,Redmi-dev/android_bootable_lk,Redmi-dev/android_bootable_lk,chirayudesai/android_bootable_bootloader_lk,RonGokhale/android_lk_bootloader,utilite2/lk,jcsullins/moboot,Foxda-Tech/polaris-bootable-bootloader-lk,chirayudesai/android_bootable_bootloader_lk,hanjae/lumiab0,mozilla-b2g/fairphone2_kernel_lk,detule/lk-g2-spr,M1cha/lktris,jsr-d9/android_kernel_lk,t2m-foxfone/kernel_lk,t2m-foxfone/android_kernel_lk,idor/dk50-bootable_bootloader_lk,M1cha/lktris,beidl/lk_umia,thornbirdblue/codeaurora_lk,oubeichen/lk-v500,M1cha/mi2_lk,MiCode/mi2_lk,chirayudesai/android_bootable_bootloader_lk,efidroid/lk,DooMLoRD/android_bootable_bootloader_lk,zhuotong/mi2_lk_NoEmmc,jbott/lk_gee,mozilla-b2g/fairphone2_kernel_lk,pichina/lk,hanjae/lumiab0,mozilla-b2g/fairphone2_kernel_lk,efidroid/lk,jbott/lk_gee,my4ndr0id/android_bootable_bootloader_lk,jcsullins/moboot,Blefish/android_bootable_bootloader_lk,CanarySolutions/little-kernel,detule/lk-g2-spr,CanarySolutions/little-kernel,hanjae/lumiab0,DooMLoRD/android_bootable_bootloader_lk,mozilla-b2g/fairphone2_kernel_lk,efidroid/lk,lg-devs/g2-bootloader,M1cha/lktris,jbott/lk_gee,Foxda-Tech/argo8-bootable-bootloader-lk,jcsullins/moboot,Foxda-Tech/argo8-bootable-bootloader-lk,idor/dk50-bootable_bootloader_lk,xndcn/moboot-for-veer,DooMLoRD/android_bootable_bootloader_lk,t2m-foxfone/android_kernel_lk,CanarySolutions/little-kernel,jcsullins/moboot,lg-devs/g2-bootloader