tools/build: Support building with glibc 2.38
Ubuntu 23.10 uses glibc 2.38. This adds strlcpy and strlcmp so we need
to remove them from the cross build environment.
Reviewed by: jrtc27 (earlier version), arichardson
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D42303
(cherry picked from commit ceefd491c7f0490515fadca2f3740cb24e3f449e)