- Move SAFE_MUTEX to be stored in config.h by configure.in (not as a flag used with compiler command line)
- Generate my_config.h in configure

BUILD/SETUP.sh:
  Remove -DSAFE_MUTEX as the following --with-debug flag will automaticly add it
BUILD/compile-ia64-debug-max:
  Remove -DSAFE_MUTEX as the following --with-debug flag will automaticly add it
configure.in:
  Move SAFE_MUTEX and SAFE_MALLOC to [my_] config.h
  Generate my_config.h as part of configure process
dbug/dbug.c:
  Include my_global.h before we undef SAFE_MUTEX
include/Makefile.am:
  Update comment. For now, lets generate my_config.h if someone deletes it after configure
mysys/my_wincond.c:
  Include my_global.h before we undef SAFE_MUTEX
mysys/my_winthread.c:
  Include my_global.h before we undef SAFE_MUTEX