Add even more pylint cleanup fixes

scripts/wk/hw/diags.py

@@ -1308,6 +1308,7 @@ def network_test():
 
 
 def ost_build_report(dev, dev_type):
+  # pylint: disable=too-many-branches
   """Build report for posting to osTicket, returns str."""
   report = []
 

scripts/wk/hw/obj.py

@@ -151,6 +151,7 @@ class CpuRam(BaseObj):
       ]
 
   def get_serial_number(self):
+    """Get Mac serial number, returns str."""
     if PLATFORM == 'Darwin':
       cmd = (
         'ioreg -c IOPlatformExpertDevice -d 2'