netpbm: Update to version 10.73.43

netpbm: Update to version 10.73.43

- IPFire-3.x
- Update from version 10.73.42 to 10.73.43
- Changelog
    10.73.43
              jpegtopnm: Many fixes to -dumpexif.  Always broken.
               (-dumpexif was new in Netpbm 9.18 (September 2001))
              pamtopng: fix -chroma option: always rejected.  Always broken.
               pamtopng was new in Netpbm 10.70 (June 2015).
              pnmtopng: fix -rgb option: always rejected.  Always broken
               -rgb was new in Netpbm 10.30 (October 2005).

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>