Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix credit configuration on Broadcom XLP CMS

The CMS output queue credit configuration register is 64 bit, so use
a 64 bit variable while updating it.
Obtained from: Venkatesh J V <venkatesh.vivekanandan@broadcom.com>

Merge XLP 3XX updates and related rework.

* Update message station (CMS) code, read queue ids from PCI header.
* Use interrupts to wakeup message handling threads on 3XX
* Update PIC code, read interrupt information from PCI header instead
of using fixed values.
* Update PCI interrupt handling for the PIC change.
* Update code for getting chip frequency, new code support XLP 3XX
* Misc style(9) fixes

In collaboration with: prabhath at netlogicmicro com (CMS/PIC)
venkatesh at netlogicmicro.com (PCI)

MIPS XLP platform code update.

* Update the hardware access register definitions and functions to bring
them in line with other Netlogic software.
* Update the platform bus to use PCI even for on-chip devices. Add a dummy
PCI driver to ignore on-chip devices which do not need driver.
* Provide memory and IRQ resource allocation code for on-chip devices
which cannot get it from PCI config.
* add support for on-chip PCI and USB interfaces.
* update conf files, enable pci and retain old MAXCPU until we can support
>32 cpus.

Approved by: re(kib), jmallett

Add MIPS platform files for Netlogic XLP SoC.

Processor, UART, PIC and Messaging Network code. Also add
sys/mips/nlm/hal for on-chip device registers.

In collaboration with: Prabhath Raman <prabhathpr at netlogicmicro com>

Approved by: bz(re), jmallett, imp(mips)