Add basic test for sparse matmul
Add basic test for sparse matmul

victorv/arrayfire,marbre/arrayfire,9prady9/arrayfire,shehzan10/arrayfire,victorv/arrayfire,9prady9/arrayfire,arrayfire/arrayfire,umar456/arrayfire,arrayfire/arrayfire,munnybearz/arrayfire,munnybearz/arrayfire,arrayfire/arrayfire,9prady9/arrayfire,marbre/arrayfire,munnybearz/arrayfire,shehzan10/arrayfire,victorv/arrayfire,9prady9/arrayfire,victorv/arrayfire,umar456/arrayfire,marbre/arrayfire,marbre/arrayfire,umar456/arrayfire,arrayfire/arrayfire,umar456/arrayfire,shehzan10/arrayfire,shehzan10/arrayfire