Comment typo fixes: pg_wchar_t should be pg_wchar.

Reported-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CA+hUKGJ5Xh0KxLYXDZuPvw1_fHX=yuzb4xxtam1Cr6TPZZ1o+w@mail.gmail.com

src/backend/utils/adt/pg_locale_libc.c

@@ -1144,7 +1144,7 @@ wcstombs_l(char *dest, const wchar_t *src, size_t n, locale_t loc)
 #endif
 
 /*
- * These functions convert from/to libc's wchar_t, *not* pg_wchar_t.
+ * These functions convert from/to libc's wchar_t, *not* pg_wchar.
  * Therefore we keep them here rather than with the mbutils code.
  */
 

src/include/utils/pg_locale.h

@@ -224,7 +224,7 @@ extern void icu_validate_locale(const char *loc_str);
 extern char *icu_language_tag(const char *loc_str, int elevel);
 extern void report_newlocale_failure(const char *localename);
 
-/* This function converts from libc's wchar_t, *not* pg_wchar_t */
+/* This function converts from libc's wchar_t, *not* pg_wchar */
 extern size_t wchar2char(char *to, const wchar_t *from, size_t tolen,
 						 locale_t loc);