net: pch_gbe: Use proper accessors to BE data in pch_ptp_match()

Sparse is not happy about handling of strict types in pch_ptp_match():

  .../pch_gbe_main.c:158:33: warning: incorrect type in argument 2 (different base types)
  .../pch_gbe_main.c:158:33:    expected unsigned short [usertype] uid_hi
  .../pch_gbe_main.c:158:33:    got restricted __be16 [usertype]
  .../pch_gbe_main.c:158:45: warning: incorrect type in argument 3 (different base types)
  .../pch_gbe_main.c:158:45:    expected unsigned int [usertype] uid_lo
  .../pch_gbe_main.c:158:45:    got restricted __be32 [usertype]
  .../pch_gbe_main.c:158:56: warning: incorrect type in argument 4 (different base types)
  .../pch_gbe_main.c:158:56:    expected unsigned short [usertype] seqid
  .../pch_gbe_main.c:158:56:    got restricted __be16 [usertype]

Fix that by switching to use proper accessors to BE data.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Flavio Suligoi <f.suligoi@asem.it>
Signed-off-by: David S. Miller <davem@davemloft.net>