again, to finally put Issue #181 to rest.

Revert some parts of r4274.  It is best not to call ut_malloc() before
srv_general_init().

mem_init(): Do not call ut_mem_init().

srv_general_init(): Initialize the memory subsystem in two phases:
first ut_mem_init(), then mem_init().  This is because os_sync_init()
and sync_init() depend on ut_mem_init() and mem_init() depends on
os_sync_init() or sync_init().

srv_parse_data_file_paths_and_sizes(),
srv_parse_log_group_home_dirs(): Remove the output parameters.  Assign
to the global variables directly.  Allocate memory with malloc()
instead of ut_malloc(), because these functions will be called before
srv_general_init().

srv_free_paths_and_sizes(): New function, for cleaning up after
srv_parse_data_file_paths_and_sizes() and
srv_parse_log_group_home_dirs().

rb://92 approved by Sunny Bains