tools build: Add test for presence of __get_cpuid() gcc builtin

The auxtrace code needed by Intel PT uses the __get_cpuid() gcc builtin,
that is not present in old systems, breaking the build.

Add a test to check for that builtin and disable AUXTRACE in those
systems.

  [acme@rhel5 linux]$  make NO_LIBPERL=1 -C tools/perf O=/tmp/build/perf install-bin
  make: Entering directory `/home/acme/git/linux/tools/perf'
    BUILD:   Doing 'make -j2' parallel build

  Auto-detecting system features:
  <SNIP>
  ...                          lzma: [ on  ]
  ...                     get_cpuid: [ OFF ]
  <SNIP>
  config/Makefile:630: Your gcc lacks the __get_cpuid() builtin, disables support for auxtrace/Intel PT, please install a newer gcc
    MKDIR    /tmp/build/perf/util/
  <SNIP>

This fixes the build on old systems such as RHEL/CentOS 5.11.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jo...