(main): Cosmetic: use X2REALLOC rather than x2realloc.

src/pr.c

@@ -2029,7 +2029,7 @@ store_char (char c)
   if (buff_current >= buff_allocated)
     {
       /* May be too generous. */
-      buff = x2realloc (buff, &buff_allocated);
+      buff = X2REALLOC (buff, &buff_allocated);
     }
   buff[buff_current++] = c;
 }