tools/nolibc/types: add poll() and waitpid() flag definitions

- POLLIN etc were missing, so poll() could only be used with timeouts.
- WNOHANG was not defined and is convenient to check if a child is still
  running

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/include/nolibc/types.h

@@ -82,6 +82,9 @@
 #define WEXITSTATUS(status) (((status) & 0xff00) >> 8)
 #define WIFEXITED(status)   (((status) & 0x7f) == 0)
 
+/* waitpid() flags */
+#define WNOHANG      1
+
 /* standard exit() codes */
 #define EXIT_SUCCESS 0
 #define EXIT_FAILURE 1
@@ -122,6 +125,13 @@ typedef struct {
 	} while (0)
 
 /* for poll() */
+#define POLLIN          0x0001
+#define POLLPRI         0x0002
+#define POLLOUT         0x0004
+#define POLLERR         0x0008
+#define POLLHUP         0x0010
+#define POLLNVAL        0x0020
+
 struct pollfd {
 	int fd;
 	short int events;