Fix inconsistent equalfuncs.c behavior for FuncCall.funcformat.

Other equalfuncs.c checks on CoercionForm fields use COMPARE_COERCIONFORM_FIELD (which makes them no-ops), but commit 40c24bf neglected to make _equalFuncCall do likewise. Fix that. This is only strictly correct if FuncCall.funcformat has no semantic effect, instead just determining ruleutils.c display formatting. 40c24bf added a couple of checks in parse analysis that could break that rule; but on closer inspection, they're redundant, so just take them out again. Per report from Noah Misch. Discussion: https://postgr.es/m/20210606063331.GC297923@rfd.leadboat.com

Author: tglsfdc

src/backend/nodes/equalfuncs.c

@@ -2420,7 +2420,7 @@ _equalFuncCall(const FuncCall *a, const FuncCall *b)
 COMPARE_SCALAR_FIELD(agg_star);
 COMPARE_SCALAR_FIELD(agg_distinct);
 COMPARE_SCALAR_FIELD(func_variadic);
-COMPARE_SCALAR_FIELD(funcformat);
+COMPARE_COERCIONFORM_FIELD(funcformat);
 COMPARE_LOCATION_FIELD(location);
 
 return true;

src/backend/parser/parse_clause.c

@@ -543,7 +543,6 @@ transformRangeFunction(ParseState *pstate, RangeFunction *r)
 !fc->agg_star &&
 !fc->agg_distinct &&
 !fc->func_variadic &&
-fc->funcformat == COERCE_EXPLICIT_CALL &&
 coldeflist == NIL)
 {
 ListCell *lc;

src/backend/parser/parse_func.c

@@ -222,7 +222,6 @@ ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
  agg_order == NIL && agg_filter == NULL &&
  !agg_star && !agg_distinct && over == NULL &&
  !func_variadic && argnames == NIL &&
- funcformat == COERCE_EXPLICIT_CALL &&
  list_length(funcname) == 1 &&
  (actual_arg_types[0] == RECORDOID ||
 ISCOMPLEX(actual_arg_types[0])));