[PATCH v2] docs/about/build-platforms: Refine the distro support policy

[Thomas Huth]

For long-term distributions that release a new version only very
seldom, we limit the support to five years after the initial release.
Otherwise, we might need to support distros like openSUSE 15 for
up to 7 or even more years in total due to our "two more years
after the next major release" rule, which is just way too much to
handle in a project like QEMU that only has limited human resources.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 v2: Only limit the maximum amount of time to five years (instead of
     four years + decreasing the amount of time after the next major
     has been released)

 docs/about/build-platforms.rst | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/docs/about/build-platforms.rst b/docs/about/build-platforms.rst
index 1c1e7b9e11..7ad95ae9ae 100644
--- a/docs/about/build-platforms.rst
+++ b/docs/about/build-platforms.rst
@@ -67,7 +67,8 @@ Non-supported architectures may be removed in the future 
following the
 Linux OS, macOS, FreeBSD, NetBSD, OpenBSD
 -----------------------------------------
 
-The project aims to support the most recent major version at all times. Support
+The project aims to support the most recent major version at all times for
+up to five years after its initial release. Support
 for the previous major version will be dropped 2 years after the new major
 version is released or when the vendor itself drops support, whichever comes
 first. In this context, third-party efforts to extend the lifetime of a distro
-- 
2.31.1