perf tools: Move units conversion/formatting routines to separate object

Out of util.h, to disentangle it a bit more.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-vpksyj3w5fk9t8s6mxmkajyr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browsers/hists.c

@@ -24,6 +24,7 @@
 #include "annotate.h"
 #include "srcline.h"
 #include "string2.h"
+#include "units.h"
 
 #include "sane_ctype.h"