Remove support for opensuse

We haven't been testing the distro for a while in CI, e.g. in
Tempest, the jobs on opensuse15 haven't been executed for a year
now.
Therefore the patch removes opensuse support from devstack.

Closes-Bug: #2002900
Change-Id: I0f5e4c644e2d14d1b8bb5bc0096d1469febe5fcc
diff --git a/lib/lvm b/lib/lvm
index 57ffb96..57d2cd4 100644
--- a/lib/lvm
+++ b/lib/lvm
@@ -129,8 +129,8 @@
     local vg=$1
     local size=$2
 
-    # Start the tgtd service on Fedora and SUSE if tgtadm is used
-    if  is_fedora || is_suse  && [[ "$CINDER_TARGET_HELPER" = "tgtadm" ]]; then
+    # Start the tgtd service on Fedora if tgtadm is used
+    if  is_fedora; then
         start_service tgtd
     fi