tests: run certain upgrade/jewel-x tests on Xenial only

This PR drops two upgrade/jewel-x test cases that are not compatible with
https://github.com/ceph/ceph/pull/14597

Signed-off-by: Nathan Cutler <ncutler@suse.com>

diff --git a/qa/suites/upgrade/jewel-x/parallel/distros b/qa/suites/upgrade/jewel-x/parallel/distros
deleted file mode 120000 (symlink)
index ca99fee..0000000
--- a/qa/suites/upgrade/jewel-x/parallel/distros
+++ /dev/null
@@ -1 +0,0 @@
-../../../../distros/supported/
\ No newline at end of file

diff --git a/qa/suites/upgrade/jewel-x/parallel/distros/centos_7.3.yaml b/qa/suites/upgrade/jewel-x/parallel/distros/centos_7.3.yaml
new file mode 120000 (symlink)
index 0000000..c79327b
--- /dev/null
+++ b/qa/suites/upgrade/jewel-x/parallel/distros/centos_7.3.yaml
@@ -0,0 +1 @@
+../../../../../distros/all/centos_7.3.yaml
\ No newline at end of file

diff --git a/qa/suites/upgrade/jewel-x/parallel/distros/ubuntu_16.04.yaml b/qa/suites/upgrade/jewel-x/parallel/distros/ubuntu_16.04.yaml
new file mode 120000 (symlink)
index 0000000..76f16d5
--- /dev/null
+++ b/qa/suites/upgrade/jewel-x/parallel/distros/ubuntu_16.04.yaml
@@ -0,0 +1 @@
+../../../../../distros/all/ubuntu_16.04.yaml
\ No newline at end of file

diff --git a/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros b/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros
deleted file mode 120000 (symlink)
index ca99fee..0000000
--- a/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros
+++ /dev/null
@@ -1 +0,0 @@
-../../../../distros/supported/
\ No newline at end of file

diff --git a/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros/centos_7.3.yaml b/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros/centos_7.3.yaml
new file mode 120000 (symlink)
index 0000000..c79327b
--- /dev/null
+++ b/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros/centos_7.3.yaml
@@ -0,0 +1 @@
+../../../../../distros/all/centos_7.3.yaml
\ No newline at end of file

diff --git a/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros/ubuntu_16.04.yaml b/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros/ubuntu_16.04.yaml
new file mode 120000 (symlink)
index 0000000..76f16d5
--- /dev/null
+++ b/qa/suites/upgrade/jewel-x/stress-split-erasure-code/distros/ubuntu_16.04.yaml
@@ -0,0 +1 @@
+../../../../../distros/all/ubuntu_16.04.yaml
\ No newline at end of file