Hide syscons-specific workaround under DEV_SC

This change is a bit ugly, but so is the coupling between the i915
driver and syscons.  It isn't worth developing a more elegant solution
only to support the legacy syscons console.
Use the standard way of printing the usage string

Sponsored by:	The FreeBSD Foundation
Remove redundant return statement after errx

MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Merge change from upstream linux kernel submitted by OpenBSD:

drm/radeon: fix-up some float to fixed conversion thinkos

Spotted by Brad Smith when porting to OpenBSD.
Noticed-by: Brad Smith <brad@comstyle.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

ref: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1cd73ff7

Remove #ifdef DUMBBELL_WIP in favor of upstream fix.

Phabric:	https://phabric.freebsd.org/D423
Reviewed by:	dumbbell, jkim
MFC after:	2 weeks
Run mtree for BSD.tests.dist during make xdev-install, if the tests are
enabled (which they are in the default configuration).  Otherwise, it
will fail because ${XDDESTDIR}/usr/include/atf-c does not exist.

MFC after:	3 days
Merge serf-1.3.6
+  Revert r2319 from serf 1.3.5: this change was making serf call handle_response
+    multiple times in case of an error response, leading to unexpected behavior.
bsd.lib.mk does not add OBJS etc to CLEANFILES so does not automatically
get them flagged as .NOPATH.  This hurts people who don't use obj dirs.
Since its clean target seprate rm's for things, use NOPATH_FILES as list
to collect things that need .NOPATH.

bsd.obj.mk will add CLEANFILES to NOPATH_FILES and do the deed if needed.

Reviewed by: sbruno
Simplify r267600, there's no need to distinguish between allocated and
inlined mbufs.

MFC after:	1 week
Rename i.MX I2C driver file.
Supress clang warning for FreeBSD printf %b and %D formats

MFC after:	2 weeks
Remove boot1.efi during clean target.
Enable Freescale i.MX I2C driver for i.MX6.
copyin/copyout should return 0 if they are truly emulating copyin/copyout behavior.

remove stray %s in printf

rewrite printf to display 64bit type without warning.
Don't save entropy inside jails.

As of r126744, we no longer feed the entropy device in jails upon
start, and collecting them is no longer useful.

PR:		conf/126744
Submitted by:	Eugene Grosbein <eugen grosbein net> (with minor changes)
MFC after:	1 week
Approved by:	so (des)
Correct typo introduced with r268855.

MFC after:	10 days
X-MFC with:	r268855
Remove #ifdef-s to reduce difference to upstream.

Pointed by:	kib

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Don't pass null kmdp to preload_search_info

On Xen PVH guests kmdp == NULL.

Submitted by:	royger
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
rewind: always clear error indicator.

Required by POSIX:
http://pubs.opengroup.org/onlinepubs/009695399/functions/rewind.html

Obtained from:	Apple Inc. (Libc 997.90.3)
MFC after:	1 week
ftello: return 1 when seeking offset on an append stream.

Obtained from:	Apple Inc. (Libc 997.90.3)
Phabric:	D442
MFC after:	2 weeks
Mostly cosmetic cleanups.

In fputs() avoid implcit casting on iov.iov_len.

MFC after:	3 days