py/emitnative: Explicitly compare comparison ops in binary_op emitter.

Without this it's possible to get a compiler error about the comparison
always being true, because MP_BINARY_OP_LESS is 0.  And it seems that gcc
optimises these 6 equality comparisons into the same size machine code as
before.

py/emitnative.c

@@ -2365,14 +2365,13 @@ STATIC void emit_native_binary_op(emit_t *emit, mp_binary_op_t op) {
         } else if (op == MP_BINARY_OP_MULTIPLY) {
             ASM_MUL_REG_REG(emit->as, REG_ARG_2, reg_rhs);
             emit_post_push_reg(emit, vtype_lhs, REG_ARG_2);
-        } else if (MP_BINARY_OP_LESS <= op && op <= MP_BINARY_OP_NOT_EQUAL) {
-            // comparison ops are (in enum order):
-            //  MP_BINARY_OP_LESS
-            //  MP_BINARY_OP_MORE
-            //  MP_BINARY_OP_EQUAL
-            //  MP_BINARY_OP_LESS_EQUAL
-            //  MP_BINARY_OP_MORE_EQUAL
-            //  MP_BINARY_OP_NOT_EQUAL
+        } else if (op == MP_BINARY_OP_LESS
+                   || op == MP_BINARY_OP_MORE
+                   || op == MP_BINARY_OP_EQUAL
+                   || op == MP_BINARY_OP_LESS_EQUAL
+                   || op == MP_BINARY_OP_MORE_EQUAL
+                   || op == MP_BINARY_OP_NOT_EQUAL) {
+            // comparison ops
 
             if (vtype_lhs != vtype_rhs) {
                 EMIT_NATIVE_VIPER_TYPE_ERROR(emit, MP_ERROR_TEXT("comparison of int and uint"));