Share linker.h between architectures

Fix arm builds broken in 44ed6adb6

SELFOUR-607: inline remaining irq path functions

SELFOUR-519: remove map_kernel_devices duplication

* move devices to static array in hardware.h
* use one higher level function to map them in.

SELFOUR-519: remove more duplication in hardware.c

* move p_reg functions up a level
* move p_reg definitions to hardware.h

Refactor duplicated code in hardware.h

One copy to rule them all.

Trivial: move printfs in handleReservedIRQ up.

This wraps the printfs in CONFIG_IRQ_REPORTING
and reduces redundancy.

SELFOUR-402: remove isReservedIRQ

While provided by each hardware platform this function is never called.

Further separate 'release' and 'verification' builds

Originally building the kernel was largely considered to be done in
one of two ways
1. Release build with no assertions, no debug symbols and no printing.
This was generally considered to be a 'verified' build
2. Debug build with assertions, debug symbols and printing

Since then various options were added, such as the 'code injection'
option, which we wanted on builds that did not have assertions or
other options that affected performance. As such it did not depend
upon a debug build and had large warning signs saying that enabling
this in a release build would not give you a verified or trusted
kernel.

Most recently the ability to print from the kernel in release mode
was added. For the same reason that tying the ability to print with
the performance reduction of various debugging was not always desireable.

This change attempts to unify the current state and have a single top
level option to enable a 'verification friendly' build. All other
options (assertions, printing, code injection) then depend upon
this configuration not being set.

Change additional int->word_t due to interraction with the C parser to ease verification

xIntroduce RELEASE_PRINTF, which allows a renamed printf (release_printf) to be used in a release build of the kernel - userful for debugging tests that only fail on a release build of the kernel

ARM: Set the XN bit on kernel mappings that do not need to be executable.

This covers the kernel stack, globals frame and device memory. We shouldn't be
executing in any of these pages, so functionality should be unaffected. This is
primarily a debugging aid.

XN: fix order of vm_attributes in init code and update apq8064

Fix IFC6410 build

The IFC6410 has too many devices to fit into the bootinfo page.
What is more, some are aligned on half-page boundaries.

Exclude devices on half-page boundaries from the bootinfo device list.

Release snapshot