sphinx: reintroduce changes for 3.1.1, 3.1.2, 3.1.3 and 3.1.4

The following changes were undo'd when the Sphinx docs were backported
in dunfell:

069c27574 Documenation: Prepared for the 3.1.1 release
bd140f0f9 Documentation: Add 3.1.1 version updates missing from previous commit
17cc71a8f Documenation: Prepared for the 3.1.2 release
1a69e2c02 Documenation: Prepared for the 3.1.3 release
8910ac1c7 Documenation: Prepared for the 3.1.4 release

In this commit, we reintroduce the content related to these patches,
but in the .rst files.

(From yocto-docs rev: a6a1b8e9df26b4b4ccf5c5c9cc3c02fa156cf81f)

Signed-off-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/documentation/ref-manual/ref-system-requirements.rst b/documentation/ref-manual/ref-system-requirements.rst
index be50d699bc..dc687d5c31 100644
--- a/documentation/ref-manual/ref-system-requirements.rst
+++ b/documentation/ref-manual/ref-system-requirements.rst
@@ -45,12 +45,18 @@ distributions:
 
 -  Ubuntu 19.04
 
+-  Ubuntu 20.04
+
 -  Fedora 28
 
 -  Fedora 29
 
 -  Fedora 30
 
+-  Fedora 31
+
+-  Fedora 32
+
 -  CentOS 7.x
 
 -  Debian GNU/Linux 8.x (Jessie)