package/fmt: bump to version 6.1.2
- License is MIT (with exception) since version 6.0.0 and
https://github.com/fmtlib/fmt/commit/5a353fa8cf147cdb13198f26145fbb026644808c
- HAVE_OPEN has been removed since version 6.1.0. and
https://github.com/fmtlib/fmt/commit/dcde089b4edaecb42c4bdd43c5b3674017a00d91
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>