Name function arguments in libc headers for Studio.

First batch of headers...

Bug: http://b/64613623
Test: builds
Change-Id: I6bc3ad79daa635456b61d03b1f43f06c433ec596
diff --git a/libc/include/bits/ioctl.h b/libc/include/bits/ioctl.h
index 53116ca..0cf87d2 100644
--- a/libc/include/bits/ioctl.h
+++ b/libc/include/bits/ioctl.h
@@ -33,7 +33,7 @@
 
 __BEGIN_DECLS
 
-int ioctl(int, int, ...);
+int ioctl(int __fd, int __request, ...);
 
 __END_DECLS