Bug#33748 my_getsystime, my_micro_time and my_micro_time_and_time broken on windows  - Fix 'my_win_init' code that handles initialization of    "query_performance_counter" and conversion from registry values to    environment strings
Bug#33748 my_getsystime, my_micro_time and my_micro_time_and_time broken on windows
 - Fix 'my_win_init' code that handles initialization of
   "query_performance_counter" and conversion from registry values to
   environment strings


mysys/my_init.c:
  - Change check of return value from 'QueryPerformanceFrequency', it
    returns 0 on error
  - Don't return from 'my_win_init' if the registry 
    key "HKEY_LOCAL_MACHINE\SOFTWARE\MySQL" doesn't exist. This caused
    the initialization of "query_performance_counter" to be bypassed unless there
    was at lest such a key.
  - Cleanup the "registry -> environment variables" from Italian comments,
    remove redundant variables and fix style.
  - Remove function 'setEnvString' and replace it with oneliner 'strxmov'

flynn1973/mariadb-aix,ollie314/server,ollie314/server,davidl-zend/zenddbi,davidl-zend/zenddbi,davidl-zend/zenddbi,ollie314/server,ollie314/server,natsys/mariadb_10.2,flynn1973/mariadb-aix,natsys/mariadb_10.2,ollie314/server,davidl-zend/zenddbi,natsys/mariadb_10.2,flynn1973/mariadb-aix,ollie314/server,davidl-zend/zenddbi,davidl-zend/zenddbi,flynn1973/mariadb-aix,flynn1973/mariadb-aix,flynn1973/mariadb-aix,slanterns/server,natsys/mariadb_10.2,davidl-zend/zenddbi,flynn1973/mariadb-aix,natsys/mariadb_10.2,ollie314/server,natsys/mariadb_10.2,ollie314/server,flynn1973/mariadb-aix,davidl-zend/zenddbi,davidl-zend/zenddbi,davidl-zend/zenddbi,ollie314/server,natsys/mariadb_10.2,flynn1973/mariadb-aix,davidl-zend/zenddbi,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,flynn1973/mariadb-aix,natsys/mariadb_10.2,flynn1973/mariadb-aix,ollie314/server,ollie314/server