hvf: Add Apple Silicon support

With Apple Silicon available to the masses, it's a good time to add support
for driving its virtualization extensions from QEMU.

This patch adds all necessary architecture specific code to get basic VMs
working, including save/restore.

Known limitations:

  - WFI handling is missing (follows in later patch)
  - No watchpoint/breakpoint support

Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210916155404.86958-5-agraf@csgraf.de
[PMM: added missing #include]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 6c20634..d7915ec 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -433,6 +433,11 @@
 F: accel/Makefile.objs
 F: accel/stubs/Makefile.objs
 
+Apple Silicon HVF CPUs
+M: Alexander Graf <agraf@csgraf.de>
+S: Maintained
+F: target/arm/hvf/
+
 X86 HVF CPUs
 M: Cameron Esfahani <dirty@apple.com>
 M: Roman Bolshakov <r.bolshakov@yadro.com>