Hi,

STAR-MC1 is an embedded processor with armv8m architecture. Majorly it
is designed to meet the requirements of AIoT application performance,
power consumption and security. Early this month, star-mc1 is supported by
the latest releases of MDK and CMSIS. For the completeness of Arm ecosystem,
it would be great if we can have star-mc1 support in official GCC as well.

Attached is the patch to support star-mc1 cpu in GCC:

* Fundamental of -mcpu=star-mc1 option
   - Based on latest upstream commit: https://gcc.gnu.org/g:3dff965cae6709a5fd1b7b05c51c3c8aba786961
   - Add star-mc1 cpu in arm-cpus.in and regenerate necessary implementation

* Include VLLDM bugfix
   - CVE-2021-35465 also affects star-mc1 configuration [1]
   - We apply quirk_vlldm strategy for star-mc1 cpu

Successfully bootstrapped and tested on arm-none-eabi.

Is it OK for trunk?

[1] https://www.cve.org/CVERecord?id=CVE-2021-35465

Regards,
jasonwucj