Match bw param behavior between wired and wireless topology files

Fixes oversight and allows for decimal values to be used for link bw
parameter in wireless topologies.

Refs: #5337
Change-Id: Iffeee64a1aa8538c56208735b349b0b6205550f6
diff --git a/minindn/wifi/minindnwifi.py b/minindn/wifi/minindnwifi.py
index bf290b8..b9e3865 100644
--- a/minindn/wifi/minindnwifi.py
+++ b/minindn/wifi/minindnwifi.py
@@ -203,9 +203,9 @@
                     continue
                 key = param.split('=')[0]
                 value = param.split('=')[1]
-                if key in ['bw', 'jitter', 'max_queue_size']:
+                if key in ['jitter', 'max_queue_size']:
                     value = int(value)
-                if key == 'loss':
+                if key in ['loss', 'bw']:
                     value = float(value)
                 params[key] = value