utils_cgroup: Fix get cgroup mount point

The new get_cgroup_mountpoint function resolve ordinary cgroup mount
points such as 'memory' to '/sys/fs/cgroup/memory cgroup'.

To fix this, I use explicit code instead of regex to match cgroup
mountpoint.

Checking get_all_controller is no longer needed since the controller
must be invalid if it's not in mount table.

get_all_controller in another function is also not needed because it is
followed by a get_cgroup_mountpoint which will raise exception if
controller is invalid.

Unit test is also added for get_cgroup_mountpoint.

Signed-off-by: Hao Liu <hliu@redhat.com>
libvirt: Fix memtune cgroup bug

The original code use 'cat' to get the content of a cgroup file. This
will cause problem if the file name contains slash '\' in it. This
fix change it by using 'open' to read.

BTW, This commit also merged some repeat helper functions.

Signed-off-by: Hao Liu <hliu@redhat.com>
libvirt-test: numatune: Fix some bugs

* VM XML omit numa entry when the placement is auto and mode is strict.
  So we need to set numa_params manually when exception happens.

* Fix typo in cfg file which causes duplicated test name. s/config/live/

* Fix typo. s/KeyError()/KeyError/

* Move restoration of cgroup to finally section to make sure cgroup can
  be restored even when exception happens.

Signed-off-by: Hao Liu <hliu@redhat.com>
libvirt: Fix schedinfo cgroup bug

This fix use 'open' instead of 'cat' to access cgroup file to prevent
problem if slash ('\') exist in file path.

If the cgroup path has a 'emulator' sub-directory. We need to trim it to
get the desired cgroup file.

Signed-off-by: Hao Liu <hliu@redhat.com>
libvirt-ci: Disable report PASS cases

PASSED cases don't need to be reported.

Signed-off-by: Hao Liu <hliu@redhat.com>