my_getopt-related style changes in myisamchk.c


include/myisam.h:
  mi_check T_xxx options massaged. T_REP_PARALLEL added
myisam/mi_check.c:
  mi_check T_xxx options massaged
myisam/myisamchk.c:
  mi_check T_xxx options massaged
  my_long_option structure reformatted
  s/(argument && \*argument=='0')/(argument == disable_my_option)/
sql/ha_myisam.cc:
  mi_check T_xxx options massaged