- Getting rid of some duplicate code in the Windows and Linux sections
- Moving the initializationa and clean-up code to connect_init_func()
  and connect_done_func(). This allows to use services provided by
  mysqld, for example my_snprintf(), which do not work in
  "__attribute__((constructor))init()".
- Removing the "__attribute__((constructor)) init()" and
  "__attribute__((destructor)) fini()" functions
- Using MariaDB's my_getpw() instead of different calls for Windows
  and Linux.
- Fixing a potentially wrong memory write in strcat() when creating
  the full connect.ini file name.
  strcat() can go outside of the buffer size when directory name is
  long enough. Using safe my_snprintf() instead.

modified:
  storage/connect/ha_connect.cc