add namespace-safe version of getauxval for internal use

src/include/sys/auxv.h

+#ifndef SYS_AUXV_H
+#define SYS_AUXV_H
+
+#include "../../../include/sys/auxv.h"
+
+#include <features.h>
+
+hidden unsigned long __getauxval(unsigned long);
+
+#endif

src/misc/getauxval.c

@@ -2,7 +2,7 @@
 #include <errno.h>
 #include "libc.h"
 
-unsigned long getauxval(unsigned long item)
+unsigned long __getauxval(unsigned long item)
 {
 	size_t *auxv = libc.auxv;
 	if (item == AT_SECURE) return libc.secure;
@@ -11,3 +11,5 @@ unsigned long getauxval(unsigned long item)
 	errno = ENOENT;
 	return 0;
 }
+
+weak_alias(__getauxval, getauxval);