Fixes for building gdbserver (and gdb) out of the box.

Bug: http://b/21695943
Change-Id: Iadb600b2ae619515d7038a4db9bf464ba31adb36
diff --git a/libc/include/sys/procfs.h b/libc/include/sys/procfs.h
index ef5b25f..b5b1a46 100644
--- a/libc/include/sys/procfs.h
+++ b/libc/include/sys/procfs.h
@@ -42,6 +42,9 @@
 typedef elf_gregset_t prgregset_t;
 typedef elf_fpregset_t prfpregset_t;
 
+typedef pid_t lwpid_t;
+typedef void* psaddr_t;
+
 __END_DECLS
 
 #endif /* _SYS_PROCFS_H_ */