Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Heat: add availability_zone"
  - Heat: add availability_zone
    
    Users would like to ensure placement of VMs on specific compute nodes so
    that the measurements are meaningful. Examples: Measure network
    performance in different scenarios (VMs in same host, in different
    hosts, across fabric, across tenants)
    
    Example:
    
    context:
      name: yardstick
      placement_groups:
        pgrp1:
          policy: "availability"
      servers:
        tg_0:
          floating_ip: true
          placement: "pgrp1"
          availability_zone: "zone2"
        vnf_0:
          floating_ip: true
          placement: "pgrp1"
          availability_zone: "zone1"
    
    Change-Id: I28a757c25ae3f5b3571ab3edd82d51ceba32c302
    Signed-off-by: Ross Brattain <ross.b.brattain@intel.com>
    

1 files changed, 0 insertions, 0 deletions

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
-Subproject bf049c61b6c11ff0756220b44b73ebbdc101366
+Subproject 9894640fb446b587c621804572eb580886bae7a