Fix minor warnings in medfilt
Fix minor warnings in medfilt

umar456/arrayfire,9prady9/arrayfire,umar456/arrayfire,arrayfire/arrayfire,munnybearz/arrayfire,munnybearz/arrayfire,arrayfire/arrayfire,9prady9/arrayfire,arrayfire/arrayfire,9prady9/arrayfire,arrayfire/arrayfire,umar456/arrayfire,munnybearz/arrayfire,umar456/arrayfire,9prady9/arrayfire