strptime: Fix style for default UTC/GMT values

Signed-off-by: Hiroshi Hatake <[email protected]>

Author: cosmo0920

src/flb_strptime.c

@@ -556,7 +556,7 @@ again:		switch (c = *fmt++) {
 					return (NULL);
 				flb_tm_gmtoff(tm) = 0;
 				tm->tm.tm_isdst = 0;
-				flb_tm_zone(tm) = "UTC";
+				flb_tm_zone(tm) = utc;
 				/* %s format does not handle timezone */
 				fields = 0xffff;         /* everything */
 			}
@@ -719,7 +719,7 @@ again:		switch (c = *fmt++) {
 					return NULL;
 				tm->tm.tm_isdst = 0;
 				flb_tm_gmtoff(tm) = 0;
-				flb_tm_zone(tm) = "GMT"; /* Original had global gmt array */
+				flb_tm_zone(tm) = gmt; /* Original had global gmt array */
 				continue;
 			case 'U':
 				if (*bp++ != 'T')
@@ -729,7 +729,7 @@ again:		switch (c = *fmt++) {
 					bp++; /* Allow "UTC" */
 				tm->tm.tm_isdst = 0;
 				flb_tm_gmtoff(tm) = 0;
-				flb_tm_zone(tm) = "UTC"; /* Original had global utc array */
+				flb_tm_zone(tm) = utc; /* Original had global utc array */
 				continue;
 			case 'Z':
 				tm->tm.tm_isdst = 0;