perf report: Fix debug messages with --call-graph option

perf report: Fix debug messages with --call-graph option

With --call-graph option, perf report can display call chains using
type, min percent threshold, optional print limit and order. And the
default call-graph parameter is 'graph,0.5,caller,function,percent'.

Before this patch, 'perf report --call-graph' shows incorrect debug
messages as below:

  # perf report --call-graph
  Invalid callchain mode: 0.5
  Invalid callchain order: 0.5
  Invalid callchain sort key: 0.5
  Invalid callchain config key: 0.5
  Invalid callchain mode: caller
  Invalid callchain mode: function
  Invalid callchain order: function
  Invalid callchain mode: percent
  Invalid callchain order: percent
  Invalid callchain sort key: percent

That is because in function __parse_callchain_report_opt(),each field of
the call-graph parameter is passed to parse_callchain_{mode,order,
sort_key,value} in turn until it meets the matching value.

For example, the order field "caller" is passed to
parse_callchain_mode() firstly and obviously it doesn't match any mode
field. Therefore parse_callchain_mode() will shows the debug message
"Invalid callchain mode: caller", which could confuse users.

The patch fixes this issue by moving the warning out of the function
parse_callchain_{mode,order,sort_key,value}.

Signed-off-by: Mengting Zhang <zhangmengting@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/1506154694-39691-1-git-send-email-zhangmengting@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>