man/man2/gettimeofday.2: Declare functions with [[deprecated]]

man/man2/gettimeofday.2: Declare functions with [[deprecated]]

As documented in the STANDARDS section, gettimeofday(2) was deprecated
in POSIX.1-2008 and removed in POSIX.1-2024.  Mark it and
settimeofday(2) with [[deprecated]], and mention clock_settime(2) as a
modern and standardized alternative to settimeofday(2).

Signed-off-by: Collin Funk <collin.funk1@gmail.com>
Message-ID: <2d37d5a9251af3c1d25cf8e73e3585a9955d5772.1750373011.git.collin.funk1@gmail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>