Added more checks.


storage/maria/ha_maria.cc:
  Let control size to my_get_opts().
storage/maria/ma_loghandler.c:
  Let control size to my_get_opts().
  Removed unused function.
  Assert to check log file size.
  Additional compilation warnings.
storage/maria/ma_loghandler.h:
  New log size bounds.
  Removed unused function.
storage/maria/unittest/ma_test_loghandler-t.c:
  Fixed test to confirm new log size bounds.