build: update to latest gnulib

Gnulib finally relaxed the isatty license, needed as first mentioned here:
https://www.redhat.com/archives/libvir-list/2012-February/msg01022.html

Other improvements include better syntax-check rules (we can delete one
of ours now that it is a duplicate) and better compiler warning usage.

* .gnulib: Update to latest, for isatty.
* cfg.mk (sc_prohibit_strncpy): Drop a now-redundant rule.
* bootstrap.conf (gnulib_modules): Add isatty.
* bootstrap: Resync from gnulib.

1 files changed, 0 insertions, 0 deletions

diff --git a/.gnulib b/.gnulib
-Subproject bb2f5640d5379c5b4eec2d62341413bbab1aa30
+Subproject 77cef2022004c4066e805da09a83b2c77f17bdd