code cleanup: add break statements in switch ()'s, (even at the last case).

source/blender/blenlib/intern/math_rotation.c

@@ -857,7 +857,8 @@ void single_axis_angle_to_mat3(float mat[3][3], const char axis, const float ang
 			mat[2][2] = 1.0f;
 			break;
 		default:
-			assert(0);
+			BLI_assert(0);
+			break;
 	}
 }