perf kbuild: remove legacy misc build variables

Remove NO_LIBAUDIT (replaced by CONFIG_LIBAUDIT)
Remove HAVE_LIBAUDIT_SUPPORT from CFLAGS (replaced by CONFIG_LIBAUDIT)
Remove HAVE_TIMERFD_SUPPORT (replaced by CONFIG_TIMERFD)
Remove HAVE_ON_EXIT_SUPPORT (replaced by CONFIG_ON_EXIT)
Remove HAVE_BACKTRACE_SUPPORT (replaced by CONFIG_BACKTRACE)
Remove HAVE_LIBNUMA_SUPPORT (replaced by CONFIG_LIBNUMA)
Remove NO_BIONIC (replaced by CONFIG_BIONIC)
perf kbuild: remove legacy libelf-related build variables

Remove NO_LIBELF (replaced by CONFIG_LIBELF)
Remove HAVE_LIBELF_SUPPORT (replaced by CONFIG_LIBELF)
Remove HAVE_LIBELF_MMAP_SUPPORT (replaced by CONFIG_LIBELF_MMAP)
Remove HAVE_LIBELF_GETPHDRNUM__SUPPORT (replaced by
CONFIG_LIBELF_GETPHDRNUM_)
perf kbuild: remove legacy libdwarf-related build variables

Remove NO_DWARF (replaced by CONFIG_LIBDWARF)
Remove HAVE_DWARF_SUPPORT (replaced by CONFIG_LIBDWARF)
perf kbuild: remove legacy script-related build variables

Remove NO_LIBPERL (replaced by CONFIG_LIBPERL)
Remove NO_LIBPYTHON (replaced by CONFIG_LIBPYTHON)
perf kbuild: final cosmetic changes

* Correctly rename internal makefile variables
* Remove makefiles in tools/perf/config which became empty and useless
* Remove builtin-cmds.h
perf kbuild: add generated Kconfig build-test cases

Thanks to the python module kconfiglib, we were able to generate build
configurations. The set is, of course, not exhaustive but for each
option, all the possible states are tested.