build: update from gnulib, for HOST_NAME_MAX on solaris 10

* gnulib: Update submodule to latest.

diff --git a/gnulib b/gnulib
index 27aa230554a630b52c2ce1540f6274c0aa4eaed1..d93c1f1b00e1dea78b919c7fb7b6ddebecfcf3a5 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 27aa230554a630b52c2ce1540f6274c0aa4eaed1
+Subproject commit d93c1f1b00e1dea78b919c7fb7b6ddebecfcf3a5