Fedora 23 supported

This change allows to use f23 without the FORCE=yes option.

Make sure you have latest kernel, or you have kernel-modules
installed for the running kernel.

f21 support will be removed when the gate jobs are upgraded
to use newer fedora version.

Change-Id: I6e3e64088187a7f6da745e3cfb07524fd31782ab
diff --git a/lib/ceph b/lib/ceph
index 29d2aca..f573136 100644
--- a/lib/ceph
+++ b/lib/ceph
@@ -116,7 +116,7 @@
 
 # check_os_support_ceph() - Check if the operating system provides a decent version of Ceph
 function check_os_support_ceph {
-    if [[ ! ${DISTRO} =~ (trusty|f21|f22) ]]; then
+    if [[ ! ${DISTRO} =~ (trusty|f21|f22|f23) ]]; then
         echo "WARNING: your distro $DISTRO does not provide (at least) the Firefly release. Please use Ubuntu Trusty or Fedora 20 (and higher)"
         if [[ "$FORCE_CEPH_INSTALL" != "yes" ]]; then
             die $LINENO "If you wish to install Ceph on this distribution anyway run with FORCE_CEPH_INSTALL=yes"