nasm: Update to version 2.15.05

nasm: Update to version 2.15.05

- Update from version 2.14.02 (Dec 2018) to 2.15.05 (Aug 2020)
- Most recent commit in git was Dec 2021
- Update of rootfile not required
- Changelog in source tarball and in git repository was last updated in 2007.
  Only option to see changes is to review the commits in
  https://github.com/netwide-assembler/nasm/commits/master

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Reviewed-by: Peter Müller <peter.mueller@ipfire.org>