release: remove binutils package data

GDB was the final GNU binutils component included in the base system,
but was removed in 2020. Nothing provides a pkgbase binutils package
any longer.

Fixes: 1c0ea326aa6d ("Retire obsolete GDB 6.1.1")
Sponsored by: The FreeBSD Foundation

(cherry picked from commit 1e4cd5ed54d73dcb8e9af92990e7bf005b9a5710)