Fix spec for mc_client_binary:cmd
Fix spec for mc_client_binary:cmd

This was causing dialyzer to complain about ebucketmigrator:init.

Change-Id: I3130d8956da78feb60103f5d39f37c4f1df079b4
Reviewed-on: http://review.membase.org/4427
Reviewed-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>

membase/ns_server,pavel-blagodov/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,pavel-blagodov/ns_server,nimishzynga/ns_server,membase/ns_server,ceejatec/ns_server,ceejatec/ns_server,membase/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,daverigby/ns_server,nimishzynga/ns_server,ceejatec/ns_server,membase/ns_server,mschoch/ns_server,vzasade/ns_server,ceejatec/ns_server,nimishzynga/ns_server,membase/ns_server,ceejatec/ns_server,pavel-blagodov/ns_server,mschoch/ns_server,ceejatec/ns_server,daverigby/ns_server,daverigby/ns_server,mschoch/ns_server,vzasade/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,mschoch/ns_server,vzasade/ns_server,pavel-blagodov/ns_server,t3rm1n4l/ns_server,vzasade/ns_server,daverigby/ns_server,daverigby/ns_server,membase/ns_server