[muxcable] Remove Xcvrd Sleep (#174)

When using redis select, xcvrd is sleeping for 100 msec which appears
unnecessary after process all content of selectable objects.

signed-off-by: Tamer Ahmed <tamer.ahmed@microsoft.com>

sonic-xcvrd/xcvrd/xcvrd_utilities/y_cable_helper.py

@@ -4,7 +4,6 @@
 """
 
 import threading
-import time
 
 from sonic_py_common import daemon_base, logger
 from sonic_py_common import multi_asic
@@ -1038,11 +1037,6 @@ def task_worker(self):
             # Use timeout to prevent ignoring the signals we want to handle
             # in signal_handler() (e.g. SIGTERM for graceful shutdown)
 
-            # A brief sleep appears necessary in this loop or any spawned
-            # update threads will get stuck. Appears to be due to the sel.select() call.
-            # TODO: Eliminate the need for this sleep.
-            time.sleep(0.1)
-
             (state, selectableObj) = sel.select(SELECT_TIMEOUT)
 
             if state == swsscommon.Select.TIMEOUT: