bugfix: fixes complex types for mean on cuda/opencl backend
bugfix: fixes complex types for mean on cuda/opencl backend

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