Standardize all the feature flags based on the HAVE_{FEATURE}_SUPPORT naming convention:

		HAVE_ARCH_X86_64_SUPPORT
		HAVE_BACKTRACE_SUPPORT
		HAVE_CPLUS_DEMANGLE_SUPPORT
		HAVE_DWARF_SUPPORT
		HAVE_ELF_GETPHDRNUM_SUPPORT
		HAVE_GTK2_SUPPORT
		HAVE_GTK_INFO_BAR_SUPPORT
		HAVE_LIBAUDIT_SUPPORT
		HAVE_LIBELF_MMAP_SUPPORT
		HAVE_LIBELF_SUPPORT
		HAVE_LIBNUMA_SUPPORT
		HAVE_LIBUNWIND_SUPPORT
		HAVE_ON_EXIT_SUPPORT
		HAVE_PERF_REGS_SUPPORT
		HAVE_SLANG_SUPPORT
		HAVE_STRLCPY_SUPPORT

Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-u3zvqejddfZhtrbYbfhi3spa@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>