Remove $FreeBSD$: two-line nroff pattern

Remove /^\.\\"\n\.\\"\s*\$FreeBSD\$$\n/

iovctl(8): Correct a typo in the manpage and correct the SYNOPSIS

PR: 246831
Submitted by: Jose Luis Duran <jlduran at gmail dot com>
Reviewed by: bcr (mentor)
Approved by: bcr (mentor)
MFC after: 7 days

Replace use of .Po Pc with the preferred .Pq for single line
enclosures in iovctl.conf(5), iovctl(8), pci(9), and
pci_iov_schema(9).

Differential Revision: https://reviews.freebsd.org/D3000
Reviewed by: wblock
Approved by: jmallett (mentor)

Add a manpage for iovctl(8)

Differential Revision: https://reviews.freebsd.org/D83
Reviewed by: wblock
MFC after: 1 month
Sponsored by: Sandvine Inc.