Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Merge r268298,r268299 from head:
Correct format string to fix build of uhsoctl when DEBUG is defined

PR: 185007
Submitted by: saper saper.info

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

mdoc sweep

Add an missing argument to open(2). If O_CREAT flag is specified,
file permission has to be specified as well.

In usr.sbin/uhsoctl/uhsoctl.c, fix a few warnings about format strings
not being literals.

MFC after: 1 week

- Fixed automatic detection of the control serial port.
- Fixed segmentation fault when an invalid network interface was given.
- More helpful message in case of wrong PIN number.

Submitted by: Fredrik Lindberg

mdoc: order prologue macros consistently by Dd/Dt/Os

Although groff_mdoc(7) gives another impression, this is the ordering
most widely used and also required by mdocml/mandoc.

Reviewed by: ru
Approved by: philip, ed (mentors)

Fix several typos in macros or macro misusage.

Found by: make manlint
Reviewed by: ru
Approved by: philip (mentor)

Always assign WARNS using ?=

- fix some nearby style bugs
- include Makefile.inc where it makes sense and reduces duplication

Approved by: ed (co-mentor)

Add a driver by Fredrik Lindberg for Option HSDPA USB devices. These differ
from standard 3G wireless units by supplying a raw IP/IPv6 endpoint rather than
using PPP over serial. uhsoctl(1) is used to initiate and close the WAN
connection.

Obtained from: Fredrik Lindberg <fli@shapeshifter.se>