Dear Mishal .. I've faced the same problem before .. I found the best way with me is to represent the wall by many hinge supports under all sides of slab, and then sum all the reactions of the longest side and dived them by the its length to find the linear load applied on the brick wall and compare it with its allowable strength.
I've done this because i think that brick wall is made of different materials and it is complicated to model it by one material inside SAP.