MFC devd-related changes

r270004
Convert devd's client socket to type SOCK_SEQPACKET.

  This change consists of two merges from projects/zfsd/head along with the
  addition of an ATF test case for the new functionality.

  sbin/devd/tests/Makefile
  sbin/devd/tests/client_test.c
        Add ATF test cases for reading events from both devd socket types.

  r266519:
  sbin/devd/devd.8
  sbin/devd/devd.cc
        Create a new socket, of type SOCK_SEQPACKET, for communicating with
        clients. SOCK_SEQPACKET sockets preserve record boundaries,
        simplying code in the client. The old SOCK_STREAM socket is retained
        for backwards-compatibility with existing clients.

  r269993:
  sbin/devd/devd.8
        Fix grammar bug.

r270019 (from bz)
Remove bogus ; at the end of the if condition in order to unbreak gcc builds
  after r270004.

  MFC after:    4 days
  X-MFX with:   r270004
MFC r267021:

  FreeBSD, historically, has always used 8-bit addresses for i2c devices
  (7-bit device address << 1), always leaving the room for the read/write
  bit.

  This commit convert ti_i2c and revert r259127 on bcm2835_bsc to make them
  compatible with 8-bit addresses.  Previous to this commit an i2c device
  would have different addresses depending on the controller it was attached
  to (by example, when compared to any iicbb(4) based i2c controller), which
  was a pretty annoying behavior.

  Also, update the PMIC i2c address on beaglebone* DTS files to match the
  new address scheme.

  Now the userland utilities need to do the correct slave address shifting
  (but it is going to work with any i2c controller on the system).

  Discussed with:	ian

MFC r267834:

  Clarify the expected usage of I2C 7-bit slave addresses on ioctl(2)
  interface.

  While here add the cross reference to iic(4) on iicbus(4).

  CR:		D210
  Suggested by:	jmg
MFC r268429: Don't install locale1.0 if MK_NLS == no.

The test locale1.0 depends on locale support; it is meaningless without a
working LC_MESSAGES.

I added an OptionalObsoleteFiles.inc entry.

PR:		181151
Submitted by:	Garrett Cooper (original version)
Sponsored by:	EMC / Isilon Storage Division