libperf: Adopt xyarray class from perf

Move the xyarray class from perf to libperf, because it's going to be
used in both.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190721112506.12306-58-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/python-ext-sources

@@ -20,7 +20,6 @@ util/namespaces.c
 ../lib/vsprintf.c
 util/thread_map.c
 util/util.c
-util/xyarray.c
 util/cgroup.c
 util/parse-branch-options.c
 util/rblist.c