tests/remote: Fix usage of a non existing variable

In monitor.py in the remote tests code there is fucntion create() that
creates standalone monitor interfaces. In this function there is an
iteration of the ifaces of the host by using the ifaces variable but
this variable is non-existing. This patch creates this variable before
its usage.

Signed-off-by: Jonathan Afek <jonathanx.afek@intel.com>

tests/remote/monitor.py

@@ -37,6 +37,7 @@ def create(devices, setup_params, refs, duts, monitors):
         try:
             host.execute(["iw", "reg", "set", setup_params['country']])
             setup_hw = setup_params['setup_hw']
+            ifaces = re.split('; | |, ', host.ifname)
             for iface in ifaces:
                 host.execute(setup_hw + " -I " + iface + " -R 1")
         except: