runtime: use correct types in __go_ptrace shim

Make the types of the addr and data arguments in the __go_ptrace shim
match the types declared in Go and the types declared by the C ptrace
function, i.e., void*. This avoids a warning about an implicit
int-to-pointer cast on some platforms.

Change-Id: Icf251b9a756e2dcff2a336ca97e109e7fbeaada7
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/262340
Trust: Than McIntosh <thanm@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/libgo/runtime/go-varargs.c b/libgo/runtime/go-varargs.c
index 9cb4a7e..d8f7dc5 100644
--- a/libgo/runtime/go-varargs.c
+++ b/libgo/runtime/go-varargs.c
@@ -122,7 +122,7 @@
 // a variadic function within glibc.
 
 long
-__go_ptrace(int request, pid_t pid, uintptr_t addr, uintptr_t data)
+__go_ptrace(int request, pid_t pid, void *addr, void *data)
 {
   return ptrace (request, pid, addr, data);
 }