tests: Minor adjustments for test data

This patch modifies some not yet used test data so that the adding a test using
this data is a clean patch and not an addition of huge file with some
adjustments in small files that will be hidden in the middle of that commit.
These changes include:

- Add system dir in vircaps2xmldata/linux-caches

  Back when data for systems with resctrl support were added they had the
  /sys/fs/system directory put into a system/ subdir of the test and
  /sys/fs/resctrl in a resctrl/ subdir of that test.  However, if we also want a
  negative test for the resctrl (requesting allocation on a system that does not
  support resctrl), we need one a test case with any sensible (with cache info)
  system/ subdir and no resctrl/ one.  Easiest way is to add a
  system -> . symlink into existing test case.

- Change default group schemata for linux-resctrl and linux-resctrl-cdp

  That way we can fit some allocation in.

- Remove one cache from resctrl-skx's schemata and make some room for
  allocations

  That system already has only one cache, so that file was wrong anyway.  We
  have a version with 2 caches already (linux-resctrl-skx-twocaches), so this
  will also add variety to future tests.

- Add some empty allocation for resctrl-skx

  Just to have slightly more coverage and variety.  We can be sure nothing bad
  happens if such allocation exists in case we have that in the tests.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>

tests/vircaps2xmldata/linux-caches/system

@@ -0,0 +1 @@
+.

tests/vircaps2xmldata/linux-resctrl-cdp/resctrl/schemata

@@ -1,2 +1,2 @@
-L3DATA:0=fffff;1=fffff
-L3CODE:0=fffff;1=fffff
+L3DATA:0=fffff;1=fc000
+L3CODE:0=ff003;1=f00ff

tests/vircaps2xmldata/linux-resctrl-skx/resctrl/schemata

@@ -1 +1 @@
-L3:0=7ff;1=7ff
+L3:0=0f0

tests/vircaps2xmldata/linux-resctrl/resctrl/schemata

@@ -1 +1 @@
-L3:0=1ffff;1=1ffff
+L3:0=1ff00;1=1ff0f