ContainerFiles/rdinfra-x86_64: install gcc 10 aarch64 toolchain

KVM tool built with GCC 11 aarch64-none-linux is expecting glibc-2.34
from buildroot, but buildroot latest (as of with 2022.08 tag) builds
only glibc-2.33. This leads to failure to launch the lkvm tool from
buildroot. As a workaround, use GCC 10 instead of GCC 11.

Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>