Added missing buffer freeing call to OpenCL SIFT
Added missing buffer freeing call to OpenCL SIFT

bkloppenborg/arrayfire,9prady9/arrayfire,pombredanne/arrayfire,pentschev/arrayfire,mrgloom/arrayfire,marbre/arrayfire,umar456/arrayfire,marbre/arrayfire,ghisvail/arrayfire,merlin-ext/arrayfire,marbre/arrayfire,bkloppenborg/arrayfire,jramapuram/arrayfire,umar456/arrayfire,bkloppenborg/arrayfire,merlin-ext/arrayfire,shehzan10/arrayfire,9prady9/arrayfire,jramapuram/arrayfire,arrayfire/arrayfire,shehzan10/arrayfire,pombredanne/arrayfire,pentschev/arrayfire,pombredanne/arrayfire,arrayfire/arrayfire,mrgloom/arrayfire,ghisvail/arrayfire,merlin-ext/arrayfire,munnybearz/arrayfire,pombredanne/arrayfire,jramapuram/arrayfire,victorv/arrayfire,bkloppenborg/arrayfire,victorv/arrayfire,umar456/arrayfire,victorv/arrayfire,shehzan10/arrayfire,marbre/arrayfire,munnybearz/arrayfire,9prady9/arrayfire,hshindo/arrayfire,hshindo/arrayfire,ghisvail/arrayfire,hshindo/arrayfire,victorv/arrayfire,hshindo/arrayfire,pentschev/arrayfire,merlin-ext/arrayfire,jramapuram/arrayfire,umar456/arrayfire,shehzan10/arrayfire,mrgloom/arrayfire,arrayfire/arrayfire,9prady9/arrayfire,munnybearz/arrayfire,arrayfire/arrayfire,pentschev/arrayfire,mrgloom/arrayfire,ghisvail/arrayfire