u.h: add intptr
diff --git a/include/u.h b/include/u.h
index ac9699c..2d29a36 100644
--- a/include/u.h
+++ b/include/u.h
@@ -144,6 +144,7 @@
 typedef uint16_t u16int;
 typedef int16_t s16int;
 typedef uintptr_t uintptr;
+typedef intptr_t intptr;
 typedef uint32_t u32int;
 typedef int32_t s32int;