tools/nolibc: unistd.h: apply __sysret() helper

Use __sysret() to shrink the whole _syscall() to oneline code.
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

tools/include/nolibc/unistd.h

@@ -56,16 +56,7 @@ int tcsetpgrp(int fd, pid_t pid)
 	return ioctl(fd, TIOCSPGRP, &pid);
 }
 
-#define _syscall(N, ...)                                                      \
-({                                                                            \
-	long _ret = my_syscall##N(__VA_ARGS__);                               \
-	if (_ret < 0) {                                                       \
-		SET_ERRNO(-_ret);                                             \
-		_ret = -1;                                                    \
-	}                                                                     \
-	_ret;                                                                 \
-})
-
+#define _syscall(N, ...) __sysret(my_syscall##N(__VA_ARGS__))
 #define _syscall_narg(...) __syscall_narg(__VA_ARGS__, 6, 5, 4, 3, 2, 1, 0)
 #define __syscall_narg(_0, _1, _2, _3, _4, _5, _6, N, ...) N
 #define _syscall_n(N, ...) _syscall(N, __VA_ARGS__)