Increase BERI loader section alignment to 16

The .text, .bss, and .data sections claimed 16-byte alignment, but were
only aligned to 8 by the linker script.

Discovered with strip(1) from elftoolchain, which performs validation
absent from the binutils strip(1).

Sponsored by:	DARPA, AFRL
Do not pre-allocate UNIT ATTENTIONs storage for every possible initiator.

Abusing ability of major UAs cover minor ones we may not account UAs for
inactive ports.  Allocate UAs storage for port and start accounting only
after some initiator from that port fetched its first POWER ON OCCURRED.

This reduces per-LUN CTL memory usage from >1MB to less then 100K.

MFC after:	1 month
Unify function names after r275458.

MFC after:	1 month
Revert device_getenv_int() for now as it duplicates resource_int_value().
We should perhaps implement a device_getenv_*() and device_setenv_*() API
as a convenience wrapper on top of resource_*_value() and resource_set_*().
Increase CTL ports limit from 128 to 256 and LUNs limit from 256 to 1024.

After recent optimizations this change is no longer blocked by CTL memory
consumption.  Those limits are still not free, but much cheaper now.

MFC after:	1 week
Relnotes:	yes
Sponsored by:	iXsystems, Inc.
Assign argemdio0 to the correct base address and assign argemdio1 to its
proper place *after* argemdio0

Correctly place arge0 and arge1 on their respective bus positions.

Sponsored by:	Nicholas Esborn <nick@desert.net>
Add libcuse and libxo.