Another zic portability fix.

I should have remembered that we can't use INT64_MODIFIER with sscanf():
configure chooses that to work with snprintf(), but it might be for our
src/port/snprintf.c implementation and so not compatible with the
platform's sscanf().  This appears to be the explanation for buildfarm
member frogmouth's continuing unhappiness with the tzcode update.

Fortunately, in all of the places where zic is attempting to read into
an int64 variable, it's reading a year which certainly will fit just fine
into an int.  So make it read into an int with %d, and then cast or copy
as necessary.

src/timezone/zic.c

@@ -23,7 +23,6 @@
 typedef int64 zic_t;
 #define ZIC_MIN PG_INT64_MIN
 #define ZIC_MAX PG_INT64_MAX
-#define SCNdZIC INT64_MODIFIER "d"
 
 #ifndef ZIC_MAX_ABBR_LEN_WO_WARN
 #define ZIC_MAX_ABBR_LEN_WO_WARN	  6
@@ -1145,7 +1144,8 @@ infile(const char *name)
 static zic_t
 gethms(char const * string, char const * errstring, bool signable)
 {
-	zic_t		hh;
+	/* PG: make hh be int not zic_t to avoid sscanf portability issues */
+	int			hh;
 	int			mm,
 				ss,
 				sign;
@@ -1162,11 +1162,11 @@ gethms(char const * string, char const * errstring, bool signable)
 	}
 	else
 		sign = 1;
-	if (sscanf(string, "%" SCNdZIC "%c", &hh, &xs) == 1)
+	if (sscanf(string, "%d%c", &hh, &xs) == 1)
 		mm = ss = 0;
-	else if (sscanf(string, "%" SCNdZIC ":%d%c", &hh, &mm, &xs) == 2)
+	else if (sscanf(string, "%d:%d%c", &hh, &mm, &xs) == 2)
 		ss = 0;
-	else if (sscanf(string, "%" SCNdZIC ":%d:%d%c", &hh, &mm, &ss, &xs)
+	else if (sscanf(string, "%d:%d:%d%c", &hh, &mm, &ss, &xs)
 			 != 3)
 	{
 		error("%s", errstring);
@@ -1179,7 +1179,7 @@ gethms(char const * string, char const * errstring, bool signable)
 		error("%s", errstring);
 		return 0;
 	}
-	if (ZIC_MAX / SECSPERHOUR < hh)
+	if (ZIC_MAX / SECSPERHOUR < (zic_t) hh)
 	{
 		error(_("time overflow"));
 		return 0;
@@ -1187,7 +1187,7 @@ gethms(char const * string, char const * errstring, bool signable)
 	if (noise && (hh > HOURSPERDAY ||
 				  (hh == HOURSPERDAY && (mm != 0 || ss != 0))))
 		warning(_("values over 24 hours not handled by pre-2007 versions of zic"));
-	return oadd(sign * hh * SECSPERHOUR,
+	return oadd(sign * (zic_t) hh * SECSPERHOUR,
 				sign * (mm * SECSPERMIN + ss));
 }
 
@@ -1374,7 +1374,9 @@ inleap(char **fields, int nfields)
 	const struct lookup *lp;
 	int			i,
 				j;
-	zic_t		year;
+
+	/* PG: make year be int not zic_t to avoid sscanf portability issues */
+	int			year;
 	int			month,
 				day;
 	zic_t		dayoff,
@@ -1389,7 +1391,7 @@ inleap(char **fields, int nfields)
 	}
 	dayoff = 0;
 	cp = fields[LP_YEAR];
-	if (sscanf(cp, "%" SCNdZIC "%c", &year, &xs) != 1)
+	if (sscanf(cp, "%d%c", &year, &xs) != 1)
 	{
 		/*
 		 * Leapin' Lizards!
@@ -1531,6 +1533,9 @@ rulesub(struct rule * rp, const char *loyearp, const char *hiyearp,
 	char	   *ep;
 	char		xs;
 
+	/* PG: year_tmp is to avoid sscanf portability issues */
+	int			year_tmp;
+
 	if ((lp = byword(monthp, mon_names)) == NULL)
 	{
 		error(_("invalid month name"));
@@ -1588,7 +1593,9 @@ rulesub(struct rule * rp, const char *loyearp, const char *hiyearp,
 						progname, lp->l_value);
 				exit(EXIT_FAILURE);
 		}
-	else if (sscanf(cp, "%" SCNdZIC "%c", &rp->r_loyear, &xs) != 1)
+	else if (sscanf(cp, "%d%c", &year_tmp, &xs) == 1)
+		rp->r_loyear = year_tmp;
+	else
 	{
 		error(_("invalid starting year"));
 		return;
@@ -1614,7 +1621,9 @@ rulesub(struct rule * rp, const char *loyearp, const char *hiyearp,
 						progname, lp->l_value);
 				exit(EXIT_FAILURE);
 		}
-	else if (sscanf(cp, "%" SCNdZIC "%c", &rp->r_hiyear, &xs) != 1)
+	else if (sscanf(cp, "%d%c", &year_tmp, &xs) == 1)
+		rp->r_hiyear = year_tmp;
+	else
 	{
 		error(_("invalid ending year"));
 		return;