[syseepromd] Prevent the syseepromd from termination (sonic-net#56)

Since the termination of the syseepromd will lead to the termination of the pmon.
Regularly try to update the eeprom data, instead of exiting the syseepromd directly when the update_eeprom_to_db return with failure.

sonic-syseepromd/scripts/syseepromd

@@ -52,10 +52,13 @@ class DaemonSyseeprom(DaemonBase):
  if self.eeprom is not None:
  try:
  return self.eeprom.read_eeprom()
- except NotImplementedError:
+ except (NotImplementedError, IOError):
  pass
 
- return self.eeprom.read_eeprom()
+ try:
+ return self.eeprom.read_eeprom()
+ except IOError:
+ pass
 
  def _wrapper_update_eeprom_db(self, eeprom):
  if self.eeprom is not None:
@@ -136,7 +139,7 @@ class DaemonSyseeprom(DaemonBase):
  # Connect to STATE_DB and post syseeprom info to state DB
  rc = self.post_eeprom_to_db()
  if rc != POST_EEPROM_SUCCESS:
- return rc
+ logger.log_error("Failed to post eeprom to database")
 
  # Start main loop
  logger.log_info("Start daemon main loop")
@@ -148,7 +151,8 @@ class DaemonSyseeprom(DaemonBase):
  self.clear_db()
  rcs = self.post_eeprom_to_db()
  if rcs != POST_EEPROM_SUCCESS:
- self.stop_event.set()
+ logger.log_error("Failed to post eeprom to database")
+ continue
 
  logger.log_info("Stop daemon main loop")