Ovmf/Xen: implement XenHypercallLib for ARM

This patch adds an implementation of XenHypercallLib for both
AArch64 and AArch32 execution modes on ARM systems.

Contributed-under: TianoCore Contribution Agreement 1.0
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16974 6f19259b-4bc3-4df7-8a09-765794883524
5 files changed