lib/srdb1: Changed OP_NEQ to use ANSI standard <>

- OP_NEQ was "!=" which works with many, but not all, SQL databases.
- One database this doesn't work with is PostgreSQL.
- <> is the standard and all databases should support it.

lib/srdb1/db_op.h

@@ -41,7 +41,7 @@
 /** operator greater than equal */
 #define OP_GEQ ">="
 /** operator negation */
-#define OP_NEQ "!="
+#define OP_NEQ "<>"
 /** bitwise AND */
 #define OP_BITWISE_AND "&"