[PATCH v6 3/4] SUPPORT.md: Document PSCI SYSTEM_SUSPEND support for guests

[Mykola Kvach <xakep.amatop@xxxxxxxxx>]

From: Mykola Kvach <mykola_kvach@xxxxxxxx>

Add a new entry under the "Virtual Hardware, QEMU" section documenting
support for the optional PSCI SYSTEM_SUSPEND function exposed to guests.

This function is available via the virtual PSCI (vPSCI) interface and
allows guest domains (domUs) to initiate system suspend operations.

The feature is currently marked as Experimental.

Signed-off-by: Mykola Kvach <mykola_kvach@xxxxxxxx>
---
Changes in v6:
- Dropped the generic guest PSCI support entry (merged in a separate patch)
- This patch now documents only the SYSTEM_SUSPEND optional function
- Reworded commit message to match the final form after rebase

Changes in v5:
- Dropped ARM/PSCI entry: this refers to internal use of PSCI SMC calls,
  which is not relevant for SUPPORT.md
- Added a dedicated entry for PSCI SYSTEM_SUSPEND instead of generic guest
  PSCI info; guest PSCI support was documented in a separate patch
---
 SUPPORT.md | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/SUPPORT.md b/SUPPORT.md
index 6a82a92189..b5ab049b52 100644
--- a/SUPPORT.md
+++ b/SUPPORT.md
@@ -962,8 +962,9 @@ Emulated PSCI interface exposed to guests. We support all 
mandatory
 functions of PSCI 1.1. See below for the list of optional PSCI call
 implemented and their status.
 
-   Status, Mandatory: Supported
-   Status, MIGRATE_INFO_TYPE: Supported
+    Status, Mandatory: Supported
+    Status, MIGRATE_INFO_TYPE: Supported
+    Status, SYSTEM_SUSPEND: Experimental
 
 ## Virtual Hardware, QEMU
 
-- 
2.48.1