move python-xml to raw_install_python.yml

The package python-xml is needed for ansible's zypper module to interact with
the zypper package management tool.

roles/ceph-defaults/defaults/main.yml:
Remove python-xml from variable suse_package_dependencies to only
install python-xml on SUSE/openSUSE if python is not found.
raw_install_python.yml already contains all the logic needed to check
if there is a valid python installation, so this is better suited there.

openSUSE Leap 15.x / SLES 15.x do no longer have /usr/bin/python,
only /usr/bin/python3, which already contains the xml module, so
nothing needs to be installed in that case.

Signed-off-by: Johannes Kastl <kastl@b1-systems.de>
(cherry picked from commit 5cf22e9b31)

group_vars/all.yml.sample

@@ -88,8 +88,7 @@ dummy:
 
 #redhat_package_dependencies: []
 
-#suse_package_dependencies:
-#  - python-xml
+#suse_package_dependencies: []
 
 # Whether or not to install the ceph-test package.
 #ceph_test: false

group_vars/rhcs.yml.sample

@@ -88,8 +88,7 @@ fetch_directory: ~/ceph-ansible-keys
 
 #redhat_package_dependencies: []
 
-#suse_package_dependencies:
-#  - python-xml
+#suse_package_dependencies: []
 
 # Whether or not to install the ceph-test package.
 #ceph_test: false

roles/ceph-defaults/defaults/main.yml

@@ -80,8 +80,7 @@ centos_package_dependencies:
 
 redhat_package_dependencies: []
 
-suse_package_dependencies:
-  - python-xml
+suse_package_dependencies: []
 
 # Whether or not to install the ceph-test package.
 ceph_test: false