fixing multipath flush problem in module_load_unload.py

multipath flush was failing due to string not matching exactly as below,

nvme                   55964  4
nvme_core             183368  5 nvme

we were expecting only : "nvme                   55964  4"
the first line only. But it is matching all the line that contain the module name.
-w option resolve this as below.

nvme                   55964  4

Signed-off-by: Naresh Bannoth <[email protected]>

io/driver/module_unload_load.py

@@ -73,7 +73,7 @@ def flush_mpath(self, mdl):
         """
         flush the multipath
         """
-        cmd = "lsmod | grep -i ^%s" % mdl
+        cmd = "lsmod | grep -iw ^%s" % mdl
         for i in range(20):
             if process.getoutput(cmd).split(" ")[-1] == '0':
                 return True