Armv8.1-m: Add pacbti support (#1147)

Armv8.1-m: Add pacbti support (#1147)

* copyright-checker: Add FreeRTOS Arm collab copyright

FreeRTOS Arm collab files shall have both Amazon's
and Arm's copyright headers. Hence, the copyright
checker is modified to check for both copyrights.

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
* armv8-m: Add support for IAR with TFM FREERTOS PORT

As the case for ARMClang, and GCC toolchains, IAR
with TFM FreeRTOS Port support is added.

Signed-off-by: Ahmed Ismail <Ahmed.Ismail@arm.com>
* armv8-m: Do not overwrite Control register value

The current ARMv8-M FreeRTOS-Kernel Port code
implementation is modified in a way that allows
the CONTROL register's value to be retained
rather than being overwritten.

This is needed for adding PACBTI support as
the special-purpose CONTROL register `PAC_EN`,
`UPAC_EN`, `BTI_EN`, and `UBTI_EN` PACBTI
enablement bits should be configured before calling
`vRestoreContextOfFirstTask()` function which currently
overwrite the value inside the CONTROL register.

Signed-off-by: Ahmed Ismail <Ahmed.Ismail@arm.com>
* armv8.1-m: Add PACBTI support to kernel non-secure implementation

In this commit, Pointer Authentication, and Branch Target
Identification Extension (PACBTI) support is added for
Non-Secure and Non-TrustZone variants of Cortex-M85
FreeRTOS-Kernel Port.

The PACBTI support is added for Arm Compiler For
Embedded, and IAR toolchains only. The support in
the kernel is not yet enabled for GNU toolchain
due to known issues.

Signed-off-by: Ahmed Ismail <Ahmed.Ismail@arm.com>
* Fix CI check

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
---------

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
Signed-off-by: Ahmed Ismail <Ahmed.Ismail@arm.com>
Co-authored-by: Ahmed Ismail <ahmism01@e133373.arm.com>
Co-authored-by: Gaurav Aggarwal <aggarg@amazon.com>