Sema: add error for signed integer division

stage1 error reads

error: division with 'i32' and 'comptime_int': signed integers must use @divTrunc, @divFloor, or @divExact

Fixes: #12339

test/cases/compile_errors/signed_integer_division.zig

@@ -0,0 +1,9 @@
+export fn foo(a: i32, b: i32) i32 {
+    return a / b;
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :2:14: error: division with 'i32' and 'i32': signed integers must use @divTrunc, @divFloor, or @divExact