perf daemon: Remove duplicate includes

sys/stat.h has been included at line 23, so remove the
duplicate one at line 27.

linux/string.h has been included at line 7, so remove the
duplicate one at line 9.

time.h has been included at line 14, so remove the
duplicate one at line 28.
Signed-off-by: NWan Jiabing <wanjiabing@vivo.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kael_w@yeah.net
Link: http://lore.kernel.org/lkml/20210323050139.287461-1-wanjiabing@vivo.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-daemon.c

@@ -6,7 +6,6 @@
 #include <linux/zalloc.h>
 #include <linux/string.h>
 #include <linux/limits.h>
-#include <linux/string.h>
 #include <string.h>
 #include <sys/file.h>
 #include <signal.h>
@@ -24,8 +23,6 @@
 #include <sys/signalfd.h>
 #include <sys/wait.h>
 #include <poll.h>
-#include <sys/stat.h>
-#include <time.h>
 #include "builtin.h"
 #include "perf.h"
 #include "debug.h"