Rework jumbo frame handling.  QAC confirmed that the controller
requires 8 bytes alignment on RX buffer.  Given that non-jumbo
frame works on any alignments I guess this DMA limitation for RX
buffer could be jumbo frame specific one.  Also I'm not sure
whether this DMA limitation is related with 64bit DMA.  Previously
age(4) disabled 64bit DMA addressing due to silent data corruption.
So we may need more testing on re-enabling 64bit DMA in future.

While I'm here, change mbuf chaining algorithm to use fixed sized
buffer and force software checksum if controller reports length
error. According to QAC, RFD is not updated at all for jumbo frame
so it works just like alc(4) controllers.  This change also added
alignment fixup for strict alignment architectures.  Because I'm
not aware of any non-x86 machines that use age(4) controllers it's
just for completeness at this moment.

Wit this change, jumbo frame should work with age(4).

Tested by:	Christian Gusenbauer < c47g <> gmx dot at >
MFC after:	1 week
Improve sysctl handler code a bit

if_*em.c:
- Whitespace cleanup.

if_igb.c:
- Fix sysctl typing so it compiles with #define notyet in sys/sysctl.h.
- Diff reduce with if_*em.c wherever possible and sensical.
- Whitespace cleanup.

Signed-off-by: Garrett Cooper <yanegomi@gmail.com>
Add gpio driver and update dts and kernel config accordingly.

Approved by: gonzo@
crunchgen: Permit use of alternative linkers.

Submitted by:	Pete Chou
MFC after:	1 week
ext2fs: Use EXT2_LINK_MAX instead of LINK_MAX

Submitted by:	Christoph Mallon
MFC after:	2 weeks
ext2fs: Use nitems().

Submitted by:	Christoph Mallon
MFC after:	2 weeks
ext2fs: Correct off-by-one errors in FFTODT() and DDTOFT().

Submitted by:	Christoph Mallon
MFC after:	2 weeks
ext2fs: Remove useless rootino local variable.

Submitted by:	Christoph Mallon
MFC after:	2 weeks
ext2fs: Remove unused em_e2fsb definition..

Submitted by:	Christoph Mallon
MFC after:	2 weeks
ext2fs: move assignment where it is not dead.

Submitted by:	Christoph Mallon
MFC after:	2 weeks
Remove two dead assignments and
make use of sc more explicit and clear

Submitted by: Christoph Mallon
Approved by: gonzo@
Build clang for little-endian arm by default. Due to size issues when built
with gcc disable CLANG_FULL for now.
Load the pfsync module if necessary.

Reviewed by:	glebius@
MFC after:	1 week
Fix depend target.
Fix some nits.
Bump .Dd for the change in r246121.

Approved by:	joel (mentor)
Remove political propaganda
Add defines to more easily allow a single threaded version of the FreeBSD
USB stack. This is useful for non-kernel purposes, like the loader.
Install <dev/agp/agpreg.h> and <dev/pci/pcireg.h> as userland headers
in /usr/include.

MFC after:	2 weeks
* Add the integer div & mod functions and ARM EABI support functions to
  libstand.
* Stop linking the ARM U-Boot loader against libgcc now libstand has the
  required symbols.