perf trace beauty fcntl: Augment the return of F_DUPFD(_CLOEXEC)

Using the existing 'fd' beautifier, now we can see the path for the just
dup'ed fd:

 18031.338 ( 0.009 ms): gnome-terminal/2472 fcntl(fd: 55, cmd: DUPFD_CLOEXEC) = 56</memfd:gdk-wayland (deleted)>

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-z0ggo126p2eobfwnjw9z16tw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>