Ignore errors from rm -rf to support high -j builds. This is, at best,
a kludge. However, it also effectively works around the issues for
high -j builds on systems that do not have the rm fixes.

A better fix would be to rmdir here, and fix the places where we're
sloppy and not list all the files we create in CLEANFILES, should
anybody have the time to chase them all to ground.
Fix build.

Pointy hat to:	melifaro
A dma tag alignment should be 1 (not 0) when a device can dma at any address.
A dma tag alignment should be 1 (not 0) when a device can dma at any address.
Backout 274170 it breaks for mips
Strengthen the sanity checking of busdma tag parameters.

It turns out an alignment of zero can lead to an endless loop in the
vm reservations code, so specifically disallow that.  The manpage says
hardware which can do dma at any address should use a value of one, which
hints at the forbiddeness of zero without exactly saying it.  Several
other conditions which could lead to insanity in working with the tag are
also checked now.

Every existing call to bus_dma_tag_create() (about 680 of them) was
eyeballed for violations of these things, and two alignment=0 glitches
were fixed.  It's possible something was missed, but overall this
shouldn't lead to any arm users suddenly experiencing failures.
Re-enable dpv(1,3): Introduced via r274116; temporarily disabled
shortly thereafter via r274124 until I could get the right recipe
down w/respect to SUBDIR_DEPEND.

Thanks to:      ngie, ian
Reviewed by:    ian
MFC after:      21 days
X-MFC-to:       stable/10 stable/9
X-MFC-with:     274116 274120 274121 274123 274144 274146
When mode isn't explicitly specified (wildcard) and inner protocol isn't
IPv4 or IPv6, assume it is the transport mode.

Reported by:	jmg
MFC after:	1 week
Sponsored by:	Yandex LLC
Add a quick and dirty script to check validity of links in elf files
Automatically build with debug symbols when building with WITH_CTF.
Otherwise there's nothing for ctfconvert to do, and it ends up emitting an
error for each object file. Also remove some redundant checks from
bsd.prog.mk and bsd.lib.mk.

Differential Revision:	https://reviews.freebsd.org/D1111
Reviewed by:		imp
SUBDIR_DEPENDS__ in lib/Makefile is not working out so well for me.
Add to using _prebuild_libs in (top-level) Makefile.inc1.
NB: Unbreak build yet again (we'll get this right eventually)

Reviewed by:	markj, ngie
Thanks to:	ian, markj, ngie, Nikolai Lifanov <lifanov@mail.lifanov.com>
MFC after:	21 days
X-MFC-to:	stable/10 stable/9
X-MFC-with:	274116 274120 274121 274123 274144 274146 274192