Fix INFO file in deb archive

INFO file generate without LC_ALL e.g. in current locale. Size must be computed with same locale, otherwise content of INFO file will be chopped of for info_size

Example:
LC_ALL=ru_RU.utf8 dpkg -I ./test.deb |wc -c
772
LC_ALL=C dpkg -I ./test.deb |wc -c
680