 e_flowlayout: typecast return value to int
 e_flowlayout: typecast return value to int

Summary:
return value is small enough, so there is no risk in casting from unsigned int to signed int.

CID: 1267211

Reviewers: devilhorns, raster, cedric, zmike

Subscribers: seoz, sachin.dev

Differential Revision: https://phab.enlightenment.org/D3179

tasn/enlightenment,rvandegrift/e,tizenorg/platform.upstream.enlightenment,rvandegrift/e,tizenorg/platform.upstream.enlightenment,tizenorg/platform.upstream.enlightenment,rvandegrift/e,tasn/enlightenment,tasn/enlightenment