split(1): Add missing static declarations.

Submitted-by: Eitan Adler <lists@eitanadler.com>
split(1): Add -d which allows a numeric suffix instead of an alphabetic one.

Submitted-by: Eitan Adler <lists@eitanadler.com>
Taken-from:   FreeBSD (r250432, r250882)
libkvm: Remove a redundant check.
fetch(1): Fix a wrong check that was always false.
mrouted(8): Fix a wrong check that was always false.
jme.4: Fix some wording and typos.
Merge branch 'master' into gsocdrm_jfree
libc/citrus: Fix an assertion (& becomes &&).
libc/citrus: Remove unneeded check (n is never < 0).
phantasia(6): Fix two operator precedence mistakes.
Merge branch 'master' into gsocdrm_github