Merge: Fix for SOL-708. Adding rmmod before modprobe in case of package upgrade

hooks/pg_dir_hooks.py

@@ -76,6 +76,7 @@ def config_changed():
     pkgs = determine_packages()
     for pkg in pkgs:
         apt_install(pkg, options=['--force-yes'], fatal=True)
+    remove_iovisor()
     load_iovisor()
     ensure_mtu()
     add_lcm_key()

hooks/pg_dir_utils.py

@@ -166,6 +166,7 @@ def remove_iovisor():
     '''
     _exec_cmd(cmd=['rmmod', 'iovisor'],
               error_msg='Error Loading IOVisor Kernel Module')
+    time.sleep(1)
 
 
 def get_mgmt_interface():