docs/ci: clean-up references for consistency

Document we have split up build-environment by distro and update the
references that exist in the code base to be correct.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240603175328.3823123-7-alex.bennee@linaro.org>

.gitlab-ci.d/custom-runners/ubuntu-22.04-aarch32.yml

@@ -1,5 +1,5 @@
 # All ubuntu-22.04 jobs should run successfully in an environment
-# setup by the scripts/ci/setup/qemu/build-environment.yml task
+# setup by the scripts/ci/setup/ubuntu/build-environment.yml task
 # "Install basic packages to build QEMU on Ubuntu 22.04"
 
 ubuntu-22.04-aarch32-all:

.gitlab-ci.d/custom-runners/ubuntu-22.04-aarch64.yml

@@ -1,5 +1,5 @@
 # All ubuntu-22.04 jobs should run successfully in an environment
-# setup by the scripts/ci/setup/qemu/build-environment.yml task
+# setup by the scripts/ci/setup/ubuntu/build-environment.yml task
 # "Install basic packages to build QEMU on Ubuntu 22.04"
 
 ubuntu-22.04-aarch64-all-linux-static:

.gitlab-ci.d/custom-runners/ubuntu-22.04-s390x.yml

@@ -1,5 +1,5 @@
 # All ubuntu-22.04 jobs should run successfully in an environment
-# setup by the scripts/ci/setup/build-environment.yml task
+# setup by the scripts/ci/setup/ubuntu/build-environment.yml task
 # "Install basic packages to build QEMU on Ubuntu 22.04"
 
 ubuntu-22.04-s390x-all-linux:

docs/devel/ci-runners.rst.inc

@@ -41,19 +41,18 @@ those hosts.  This would look like::
 Build environment
 ~~~~~~~~~~~~~~~~~
 
-The ``scripts/ci/setup/build-environment.yml`` Ansible playbook will
-set up machines with the environment needed to perform builds and run
-QEMU tests.  This playbook consists on the installation of various
-required packages (and a general package update while at it).  It
-currently covers a number of different Linux distributions, but it can
-be expanded to cover other systems.
+The ``scripts/ci/setup/$DISTRO/build-environment.yml`` Ansible
+playbook will set up machines with the environment needed to perform
+builds and run QEMU tests. This playbook consists on the installation
+of various required packages (and a general package update while at
+it).
 
 The minimum required version of Ansible successfully tested in this
 playbook is 2.8.0 (a version check is embedded within the playbook
 itself).  To run the playbook, execute::
 
   cd scripts/ci/setup
-  ansible-playbook -i inventory build-environment.yml
+  ansible-playbook -i inventory $DISTRO/build-environment.yml
 
 Please note that most of the tasks in the playbook require superuser
 privileges, such as those from the ``root`` account or those obtained