Change dt_cg_agg_lquantize() arg check to agree with message

We check limitval<baseval, but the error message is "base must
be less than limit".  Make the check more stringent to agree
with the error message.

Note that this behavior dates back to DTrace v1:
     # dtrace -n 'BEGIN {@ = lquantize(8, 4, 4); exit(0) }'
     dtrace: invalid probe specifier:
     lquantize( ) step (argument #3) too large:
     must have at least one quantization level
That is, the arguments pass the check but are then caught by a
later, rather confusing, message.

Add a test to catch this case.

Signed-off-by: Eugene Loh <eugene.loh@oracle.com>
Reviewed-by: Kris Van Hees <kris.van.hees@oracle.com>

libdtrace/dt_cg.c

@@ -3457,7 +3457,7 @@ dt_cg_agg_lquantize(dt_pcb_t *pcb, dt_ident_t *aid, dt_node_t *dnp,
 		dnerror(arg2, D_LQUANT_LIMVAL, "lquantize( ) argument #2 must "
 			"be a 32-bit quantity\n");
 
-	if (limitval < baseval)
+	if (limitval <= baseval)
 		dnerror(dnp, D_LQUANT_MISMATCH,
 			"lquantize( ) base (argument #1) must be less than "
 			"limit (argument #2)\n");

test/unittest/aggs/err.D_LQUANT_MISMATCH.lqbadarg2.d

@@ -0,0 +1,33 @@
+/*
+ * Oracle Linux DTrace.
+ * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
+ * Licensed under the Universal Permissive License v 1.0 as shown at
+ * http://oss.oracle.com/licenses/upl.
+ */
+
+/*
+ * ASSERTION:
+ * 	Upper bound must be greater than lower bound argument
+ *
+ * SECTION: Aggregations/Aggregations
+ */
+
+#pragma D option quiet
+
+BEGIN
+{
+	i = 0;
+}
+
+tick-1
+/i < 1000/
+{
+	@ = lquantize(i, 1100, 1100, -100 );
+	i += 100;
+}
+
+tick-1
+/i == 1000/
+{
+	exit(0);
+}