Do not generate data symbols for enums

With clang 11 these become bss symbols rather than commons, resulting in
multiple definition errors at link time. gcc 10 is likely to expose the
same issue.

Signed-off-by: Stefan O'Rear <sorear@fastmail.com>

replacing all ifndef with pargma once

All the kernel header files now use pargma once rather than the ifndef,
as the pre-processed C files do not change while header files
are protected with pargma once. This will also solve any naming issues
caused by ifndef.

Convert license tags to SPDX identifiers

This commit also converts our own copyright headers to directly use
SPDX, but leaves all other copyright header intact, only adding the
SPDX ident. As far as possible this commit also merges multiple
Data61 copyright statements/headers into one for consistency.

mcs: timeout exceptions

- Add seL4_TCB_SetTimeoutEndpoint
- implement timeout exceptions

mcs: configurable scheduling context size

This allows users to define custom amounts of refills without
increasing the scheduling context size system wide.

also add libsel4 functions for refill size

mcs: associate scheduling context + ntfn

This commit allows scheduling contexts to be bound
to notification objects. When a passive server
receives a notification it will receive the scheduling
context from the notification. When the server
blocks the scheduling context is returned.

mcs: scheduling context donation over ipc

After this commit, threads blocked on an endpoint can recieve a
scheduling context from the thread that wakes the blocked thread.

mcs: add periodic scheduling

This commit adds periodic scheduling with sporadic servers.

mcs: Add a scheduling context object

This is the first part of the seL4 MCS. This commit:

* adds a scheduling context object. Threads without scheduling
context objects cannot be scheduled.
* replaces tcbTimeSlice with the scheduling context object
* adds seL4_SchedControl caps for each core
* adds seL4_SchedControl_Configure which allows users to configure
amount of ticks a scheduling context has, and set a core for the
scheduling context.
* adds seL4_SchedContext_Bind, Unbind and UnbindObject, which allows
a tcb to be bound to a scheduling context.

libsel4: add seL4_VspaceBits

This constant represents the size of the root page table.

More standard constant name, moved ASID constants to arch generic files

Add seL4_UserTop and move kernelBase to the arch level

- seL4_UserTop is a new constant which represents the top of virtual
memory available to user level
- this commit also rationalises several constants (USER_TOP, kernelBase)
and moves them to the arch level, such that ports only need to define
seL4_UserTop.

x86: Increase TCB size for large xsave regions

Declare and check IPC buffer size

Adds a named constant of the IPC buffer size bits that can be used when checking the
size/alignment of an IPC buffer. This constant has a compile time assertion to ensure
it corresponds to the actual IPC buffer

libsel4: fix licenses

- some were incorrectly marked GPL (libsel4 is BSD)
- update NICTA --> DATA61 etc
- fix tags D61 --> DATA61
- update year to 2017

SELFOUR-879: expose index and entry constants

libsel4: Add seL4_FastMessageRegisters

This allows benchmarks and utility code to only set registers in the ipc
buffer as required.

s/D61/DATA61/ in license headers for consistency

x64: VT-x related cap and object definitions

* Adds object and cap definitions for VT-x structures (VCPU and EPT).
* Extends the asid_map implementation to support ASIDs in the EPT
* Adds size definitions for VCPU and EPT objects

SELFOUR-413: refactor libsel4 fault API

This is a *breaking API change*

This commit:

* makes seL4_Fault_tag_t common between the kernel and libsel4
* deprecates the existing functions from sel4/messages.h includes
* introduces a new fault API in sel4/faults.h and
* sel4/sel4_arch/faults.h
* deprecates seL4_GetTag(), as the function did not work without
the user calling seL4_SetTag() first (seL4_MessageInfo is passed
in registers and not set in the IPC buffer)
* removes previously deprecated functions (deprecated prior to 3.0.0)
* updates the seL4 manual to reflect the changes

Replace #pragma once with include guards

Defined untyped size ranges in libsel4

x64/libsel4: Add x64 libsel4 implementation