Fixed some missing this_program_does_not_exist constants.

lib/modules/Sql.pmod/mysqls.pike

@@ -43,4 +43,7 @@ void create(string host,
 
   ::create(host||"", db||"", user||"", password||"", options);
 }
+
+#else
+constant this_program_does_not_exist = 1;
 #endif

lib/modules/Sql.pmod/mysqls_result.pike

@@ -8,4 +8,6 @@ constant dont_dump_program = 1;
 
 inherit Sql.mysql_result;
 
+#else
+constant this_program_does_not_exist = 1;
 #endif

lib/modules/Sql.pmod/oracle.pike

@@ -17,4 +17,7 @@ string server_info()
 {
   return "Oracle";
 }
+
+#else
+constant this_program_does_not_exist = 1;
 #endif /* constant(Oracle.oracle) */