bp: remove unnecessary opening/closing of master db from xdc_vbucket_rep
bp: remove unnecessary opening/closing of master db from xdc_vbucket_rep

Change-Id: Ia350ba648740b4aacca52dabf2235d202ecf96a1
Orig-Reviewed-on: http://review.couchbase.org/41934
Reviewed-on: http://review.couchbase.org/42997
Reviewed-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>

mschoch/ns_server,ceejatec/ns_server,mschoch/ns_server,nimishzynga/ns_server,membase/ns_server,mschoch/ns_server,ceejatec/ns_server,membase/ns_server,nimishzynga/ns_server,nimishzynga/ns_server,ceejatec/ns_server,membase/ns_server,ceejatec/ns_server,membase/ns_server,nimishzynga/ns_server,membase/ns_server,ceejatec/ns_server,nimishzynga/ns_server,membase/ns_server,mschoch/ns_server,ceejatec/ns_server,mschoch/ns_server,mschoch/ns_server,nimishzynga/ns_server