Workaround for strict flags and release build compilation

@campbellbarton, it's really helpful to have strict flags enabled
for release builds as well -- especially when you're working in areas
which are heavily using least squares solvers.

For now made it so blender compiles, but it could be better solution here.

source/blender/bmesh/operators/bmo_inset.c

@@ -156,6 +156,7 @@ static void bm_loop_customdata_merge(
 	BLI_assert(l_a_outer->f == l_a_inner->f);
 	BLI_assert(l_b_outer->f == l_b_inner->f);
 
+	(void) e_connect;
 	BLI_assert(BM_edge_in_face(e_connect, l_a_inner->f));
 	BLI_assert(BM_edge_in_face(e_connect, l_b_inner->f));