tools/nolibc: drop custom definition of struct rusage

A future commit will include linux/resource.h, which will conflict with
the private definition of struct rusage in nolibc.
Avoid the conflict by dropping the private definition and use the one
from the UAPI headers.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/20231123-nolibc-rlimit-v1-1-a428b131de2a@weissschuh.net/Acked-by: Willy Tarreau <w@1wt.eu>

tools/include/nolibc/types.h

@@ -13,6 +13,7 @@
 #include <linux/stat.h>
 #include <linux/time.h>
 #include <linux/wait.h>
+#include <linux/resource.h>
 
 
 /* Only the generic macros and types may be defined here. The arch-specific
@@ -178,26 +179,6 @@ struct linux_dirent64 {
 	char           d_name[];
 };
 
-/* needed by wait4() */
-struct rusage {
-	struct timeval ru_utime;
-	struct timeval ru_stime;
-	long   ru_maxrss;
-	long   ru_ixrss;
-	long   ru_idrss;
-	long   ru_isrss;
-	long   ru_minflt;
-	long   ru_majflt;
-	long   ru_nswap;
-	long   ru_inblock;
-	long   ru_oublock;
-	long   ru_msgsnd;
-	long   ru_msgrcv;
-	long   ru_nsignals;
-	long   ru_nvcsw;
-	long   ru_nivcsw;
-};
-
 /* The format of the struct as returned by the libc to the application, which
  * significantly differs from the format returned by the stat() syscall flavours.
  */