remove all trailing blank lines

by running this command:
git ls-files -z | xargs -0 perl -pi -0777 -e 's/\n\n+$/\n/'
This is in preparation for a more strict make syntax-check
rule that will detect trailing blank lines.

tests/confdata/libvirtd.conf

@@ -218,5 +218,3 @@ tls_allowed_dn_list = ["DN1", "DN2"]
 #
 # By default, no Username's are checked
 sasl_allowed_username_list = ["joe@EXAMPLE.COM", "fred@EXAMPLE.COM" ]
-
-