OpenSBI v1.3.1 Released

[Anup Patel]

Hi All,

The OpenSBI v1.3.1 is now available on GitHub at:
https://github.com/riscv-software-src/opensbi/releases

This intermediate release has:

* ACLINT driver fix for disabled CPUs
* SBI PMU fix for out-of-bound access
* Designware GPIO driver

Overall, this is our first intermediate release with a crucial
ACLINT driver fix.

In future, we may do an intermediate release only if there
are crucial fixes which were missed out in the preceding
release.

Best Regards,
Anup