Workaround a GCC warning to unbreak ARM build.

Reported by:	ian
Add gpio and clock bits for A10/A20's EMAC ethernet controller driver, such as:
- EMAC gpio configuration
- EMAC clock activation

Approved by:	stas (mentor)
Add Static Random Access Memory controller driver for A10/A20.
A10/A20's SRAM is used by devices, such as CPU, EMAC,
for extra fast memory or as cache.

Approved by:	stas (mentor)
Add EMAC 10/100 Ethernet controller driver for A10/A20.
It is available mostly in A10 devices like Hackberry, Marsboard,
Mele A1000, A2000, A100 HTPC, cubieboard1 and A20 device
like cubieboard2.
TX performance can be improved using both channels 0 and 1.
RX performance is poor and needs improvement with the assistance of
external DMA controller in case there is bulk TCP receiver.

Reviewed by:	yongari@
Approved by:	stas (mentor)
Add EMAC and SRAM controller entries to FDT.
Add EMAC device to kernel config files and
enable EMAC, SRAM drivers for build.

Approved by:	stas (mentor)
Use the standard __used macro instead of a bare __attribute__.

Submitted by:	bde
Add a missing semicolong, noticed by the gnu dt compiler.
Add note about dtc switch.
Include kbd(4) when vt(4) is enabled as on other platforms.

Reported by:	Anton Shterenlikht
Document the fact that OpenSSH default configuration requires Capsicum
capability mode support in kernel, which have been worked around later
but it's still recommended to have it enabled.
Increase MAXLINE to deal with longer paths.

Obtained from:	Juniper Networks, Inc.
Replace use of ${.CURDIR} by ${LIBC_SRCTOP} and define ${LIBC_SRCTOP}
if not already defined. This allows building libc from outside of
lib/libc using a reach-over makefile.

A typical use-case is to build a standard ILP32 version and a COMPAT32
version in a single iteration by building the COMPAT32 version using a
reach-over makefile.

Obtained from:	Juniper Networks, Inc.
Fix syntax errors and warnings emitted by the GPL dtc.
When reading physical memory, make sure to access it using the right
memory attributes. The same applies to the mmap(2) interface. Not
doing so results in machine checks.

We find the memory attributes in the EFI memory map, as queried by
mem_phys2virt().
Naming consistency fix. The routing code defines
RADIX_NODE_HEAD_LOCK as grabbing the write lock,
but RADIX_NODE_HEAD_LOCK_ASSERT as checking the read lock.

Submitted by:	Vijay Singh <vijju.singh at gmail.com>
MFC after:	1 month
[automated] Merge in upstream-github/master