perf tools: Fixup get_current_dir_name() compilation

strdup() prototype doesn't live in stdlib.h .

Add limits.h for PATH_MAX definition as well.

This fixes the build on Android.

Signed-off-by: Alexey Dobriyan (SK hynix) <[e-mail]>
Acked-by: Namhyung Kim <[e-mail]>
Link: http://lore.kernel.org/lkml/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/get_current_dir_name.c

···
 //
 #ifndef HAVE_GET_CURRENT_DIR_NAME
 #include "get_current_dir_name.h"
+#include <limits.h>
+#include <string.h>
 #include <unistd.h>
-#include <stdlib.h>
 
 /* Android's 'bionic' library, for one, doesn't have this */