[PATCH v3] SUPPORT: downgrade Physical CPU Hotplug to Experimental

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

From: Stefano Stabellini <stefano.stabellini@xxxxxxx>

The feature is not commonly used, and we don't have hardware to test it,
not in OSSTest, not in Gitlab, and not even ad-hoc manually by community
members. We could use QEMU to test it, but even that it is known not to
work.

Also take the opportunity to rename the feature to "ACPI CPU Hotplug"
for clarity.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxx>
---
Changes in v3:
- add note to CHANGELOG.md
---
 CHANGELOG.md | 2 ++
 SUPPORT.md   | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 24636b8eaf..e33cf4e1b1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,8 @@ The format is based on [Keep a 
Changelog](https://keepachangelog.com/en/1.0.0/)
    known user doesn't use it properly, leading to in-guest breakage.
  - The "dom0" option is now supported on Arm and "sve=" sub-option can be used
    to enable dom0 guest to use SVE/SVE2 instructions.
+ - Physical CPU Hotplug downgraded to Experimental and renamed "ACPI CPU
+   Hotplug" for clarity
 
 ### Added
  - On x86, support for features new in Intel Sapphire Rapids CPUs:
diff --git a/SUPPORT.md b/SUPPORT.md
index 3461f5cf2f..3472b6edfa 100644
--- a/SUPPORT.md
+++ b/SUPPORT.md
@@ -46,9 +46,9 @@ For the Cortex A77 r0p0 - r1p0, see Errata 1508412.
 
 ## Host hardware support
 
-### Physical CPU Hotplug
+### ACPI CPU Hotplug
 
-    Status, x86: Supported
+    Status, x86: Experimental
 
 ### Physical Memory
 
-- 
2.25.1