infra/change-log: update change log for RD-INFRA-2021.05.27 release

Update change log for the RD-INFRA-2021.05.27 release. The platforms
that are receiving software updates as part of this release are RD-N2
and RD-N2-Cfg1. Document the changes in the software stack for these
two platforms.

Signed-off-by: Thomas Abraham <thomas.abraham@arm.com>
Change-Id: I222b82370437ba588a357b1e509ef347d426a666

docs/infra/change-log.rst

@@ -9,6 +9,25 @@ releases. The changes introduced with each of the release is listed under the
 the corresponding release tag. The release tag format is RD-INFRA-YYYY.MM.DD.
 
 
+RD-INFRA-2021.05.27
+-------------------
+- Release targetted for RD-N2 and RD-N2-Cfg1 platform software updates.
+- Improves the support for multiple IO Macros. SMMU in the IO macro path has
+  been enabled. Multiple PCIe root bridges (connedted to the various IO macros)
+  can be assigned to a single PCIe segment.
+- Enabled the use of buildroot and virtualization tests.
+- MCP ram firmware is functional on RD-N2 and RD-N2-Cfg1.
+- Validated latest distro versions - Fedora 34, Debian 10.9 and Ubuntu 20.04.
+- SCP, TF-A, EDKII, EDKII platforms, Linux kernel components are rebased to
+  the respective latest upstream master branche as on 26th May 2021.
+- WinPE boot has been removed from the list of supported features because
+  LPI is enabled in the software stack and there are known issues with
+  WinPE boot when LPI is enabled.
+- Tests completed for RD-N2 and RD-N1-Cfg1 platforms include Busybox boot,
+  Buildroot boot, Secure Boot, Distro boot, ACS tests (SBSA and SBBR) and
+  Virtualization.
+
+
 RD-INFRA-2021.04.30
 -------------------
 - Release targetted for RD-N2 and RD-N2-Cfg1 platform software updates.