[PATCH] docs/system: clarify deprecation scheduled

[Stefan Hajnoczi <stefanha@redhat.com>]

The sentence explaining the deprecation schedule is ambiguous. Make it
clear that a feature deprecated in the Nth release is guaranteed to
remain available in the N+1th release. Removal can occur in the N+2nd
release or later.

As an example of this in action, see commit
25956af3fe5dd0385ad8017bc768a6afe41e2a74 ("block: Finish deprecation of
'qemu-img convert -n -o'"). The feature was deprecated in QEMU 4.2.0. It
was present in the 5.0.0 release and removed in the 5.1.0 release.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 docs/system/deprecated.rst | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst
index 851dbdeb8a..fecfb2f1c1 100644
--- a/docs/system/deprecated.rst
+++ b/docs/system/deprecated.rst
@@ -4,9 +4,9 @@ Deprecated features
 In general features are intended to be supported indefinitely once
 introduced into QEMU. In the event that a feature needs to be removed,
 it will be listed in this section. The feature will remain functional
-for 2 releases prior to actual removal. Deprecated features may also
-generate warnings on the console when QEMU starts up, or if activated
-via a monitor command, however, this is not a mandatory requirement.
+for 1 more release after deprecation. Deprecated features may also generate
+warnings on the console when QEMU starts up, or if activated via a monitor
+command, however, this is not a mandatory requirement.
 
 Prior to the 2.10.0 release there was no official policy on how
 long features would be deprecated prior to their removal, nor
-- 
2.26.2