perf trace beauty open flags: Move RDRW to the start of the output

perf trace beauty open flags: Move RDRW to the start of the output

We were getting:

 62597.859 ( 0.005 ms): TaskSchedulerF/18107 fcntl(fd: 194, cmd: GETFL) = LARGEFILE|RDWR

Instead of the more familiar (from looking at strace output):

 62597.859 ( 0.005 ms): TaskSchedulerF/18107 fcntl(fd: 194, cmd: GETFL) = RDWR|LARGEFILE

Fix it.

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-d4d9nd88t4bu9y9odbrcb5z6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>