mcs: Rename CONFIG_KERNEL_RT to CONFIG_KERNEL_MCS

This is to be consistent with the name defined in the kernel.

runner: simplify integrity label handling

This removes set_integrity_label and merges it into alloc, alloc_obj.

We also change register_shared_variable so that it now allocates frames
with a sensible default label. This allows us to drop the manually set
labels from the built-in shared mem templates.

templates: specify connector label when allocating shared memory

This modifies register_shared_variable, etc. to accept a label argument
and updates shared memory templates to pass in the connector label.

As shared frame objects are now allocated under the correct labels,
we no longer need to fix them in object_label_mapping prior to the
integrity verification.

Allow templates to manually set integrity labels for objects

This is needed by some connector templates because they allocate
private objects for the parent component. We need to inform the
capDL verification template that these objects are owned by the
component's label.

Fixed for seL4Notification's internal lock objects; other connectors
will undoubtedly also need updating.

Modify shared regions to use AddrSpaceAllocator

This updates register_shared_variable to use AddrSpaceAllocator instead
of shmem. The relevant filter functions have also been removed.

Change Camkes alignment and section linking policy

There are now special sections created by the Camkes linker script that
are aligned to each of the architecture page sizes. Symbols that require
a certain alignment in order to be backed by an underlying seL4 frame of
a certain size should declare to be in the section of that size. The
purpose of this is to drastically simplify the linking policy shared
between Camkes and the capdl python scripts that would create the
address space objects.

The linker script requirement is because a compiler/assembler is not required to
respect the `align` attribute above a certain small size and any
alignment requirements on the order of page sizes needs to be specified
by a linker script.

These changes make it possible to remove some architecture special cases
that exist in Camkes templates, which is why they are removed.

It is assumed that any of the special policy associated with the special
section names: guarded, shared_*, ignore_* and persistent can still be
implemented by using the new section name with the same alignment, eg
align_12bit for all symbols that require 4k guard pages.

Make error-handler.c a macro

Moves the 'error-handler.c' template logic into a 'helpers' template as a macro with
arguments, instead of a template file that is 'include'd and relies on peeking at
global variables to simulate argument passing.

Fix licenses

CAMKES-560: Add support for new-rt APIs to next

Replace instances of seL4_Recv, seL4_SignalRecv, seL4_Send, with
RT-compliant versions that operate on reply object caps.

Replaced seL4Asynch with seL4Notification

Breaking change that replaces the sel4Asynch* connectors with
corresponding seL4Notification* connectors.

Replaced seL4_Wait with seL4_Recv in .c files (including templates)

Refactored parser init commit.

Renamed seL4Asynch connector to seL4Notification, keeping support for seL4Asynch