perf tools: Remove string.h, unistd.h and sys/stat.h from util.h

Not needed in this header, added to the places that need FILE,
putchar(), access() and a few other prototypes.

Link: http://lkml.kernel.org/n/tip-xxtdsl6nsna82j7puwbdjqhs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/arm/util/cs-etm.c

@@ -33,6 +33,7 @@
 #include "../../util/cs-etm.h"
 
 #include <stdlib.h>
+#include <sys/stat.h>
 
 #define ENABLE_SINK_MAX	128
 #define CS_BUS_DEVICE_PATH "/bus/coresight/devices/"

tools/perf/arch/arm64/util/dwarf-regs.c

@@ -10,6 +10,7 @@
 
 #include <errno.h>
 #include <stddef.h>
+#include <string.h>
 #include <dwarf-regs.h>
 #include <linux/ptrace.h> /* for struct user_pt_regs */
 #include <linux/stringify.h>