use basename for setting hostname

plugins/guests/suse/cap/change_host_name.rb

@@ -8,8 +8,8 @@ module VagrantPlugins
           if !comm.test("hostname -f | grep '^#{name}$'", sudo: false)
             basename = name.split(".", 2)[0]
             comm.sudo <<-EOH.gsub(/^ {14}/, '')
-              echo '#{name}' > /etc/HOSTNAME
-              hostname '#{name}'
+              echo '#{basename}' > /etc/HOSTNAME
+              hostname '#{basename}'
 
               # Prepend ourselves to /etc/hosts
               grep -w '#{name}' /etc/hosts || {