file: fix warning

modules/access/file.c

@@ -325,7 +325,7 @@ ssize_t FileRead( access_t *p_access, uint8_t *p_buffer, size_t i_len )
         struct stat st;
 
         if ((fstat (fd, &st) == 0)
-         && (p_access->info.i_size != st.st_size))
+         && (p_access->info.i_size != (uint64_t)st.st_size))
         {
             p_access->info.i_size = st.st_size;
             p_access->info.i_update |= INPUT_UPDATE_SIZE;