Fix windows compile issue for opencl context handling
Fix windows compile issue for opencl context handling

asifmadnan/arrayfire,pavanky/arrayfire,Keno/arrayfire,pavanky/arrayfire,victorv/arrayfire,linan7788626/arrayfire,Keno/arrayfire,arrayfire/arrayfire,munnybearz/arrayfire,glehmann/arrayfire,linan7788626/arrayfire,unbornchikken/arrayfire,9prady9/arrayfire,HolyGeneralK/arrayfire,pavanky/arrayfire,umar456/arrayfire,bkloppenborg/arrayfire,unbornchikken/arrayfire,9prady9/arrayfire,ghisvail/arrayfire,mrgloom/arrayfire,hshindo/arrayfire,munnybearz/arrayfire,bkloppenborg/arrayfire,victorv/arrayfire,shehzan10/arrayfire,9prady9/arrayfire,hshindo/arrayfire,HolyGeneralK/arrayfire,Keno/arrayfire,pombredanne/arrayfire,pentschev/arrayfire,arrayfire/arrayfire,mrgloom/arrayfire,asifmadnan/arrayfire,merlin-ext/arrayfire,asifmadnan/arrayfire,marbre/arrayfire,ghisvail/arrayfire,jramapuram/arrayfire,merlin-ext/arrayfire,pombredanne/arrayfire,unbornchikken/arrayfire,pentschev/arrayfire,marbre/arrayfire,jramapuram/arrayfire,glehmann/arrayfire,victorv/arrayfire,umar456/arrayfire,shehzan10/arrayfire,unbornchikken/arrayfire,pombredanne/arrayfire,pavanky/arrayfire,bkloppenborg/arrayfire,Keno/arrayfire,merlin-ext/arrayfire,pentschev/arrayfire,shehzan10/arrayfire,pombredanne/arrayfire,mrgloom/arrayfire,arrayfire/arrayfire,munnybearz/arrayfire,linan7788626/arrayfire,shehzan10/arrayfire,jramapuram/arrayfire,umar456/arrayfire,ghisvail/arrayfire,pentschev/arrayfire,umar456/arrayfire,HolyGeneralK/arrayfire,marbre/arrayfire,marbre/arrayfire,asifmadnan/arrayfire,merlin-ext/arrayfire,jramapuram/arrayfire,bkloppenborg/arrayfire,hshindo/arrayfire,hshindo/arrayfire,ghisvail/arrayfire,linan7788626/arrayfire,HolyGeneralK/arrayfire,9prady9/arrayfire,victorv/arrayfire,mrgloom/arrayfire,arrayfire/arrayfire