Reuse operation rule for operation2 rule in parse.y

[S-H-GAMELINKS]

In parse.y, operation and operation2 pattern rule has similar pattern.

operation	: tIDENTIFIER
		| tCONSTANT
		| tFID
		;
operation2	: tIDENTIFIER
		| tCONSTANT
		| tFID
		| op
		;

It may be more simpler to reuse operation rule.

operation	: tIDENTIFIER
		| tCONSTANT
		| tFID
		;

operation2	: operation
		| op
		;