qemu/osdep: Remove the need for qemu_init_auxval

Instead of getting backup auxv data from the env pointer given to main,
read it from /proc/self/auxv.  We can do this at any time, so we're not
tied to any ordering wrt a call to qemu_init_auxval from main.

Tested-by: Tom Musta <tommusta@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>

linux-user/main.c

@@ -3829,7 +3829,6 @@ int main(int argc, char **argv, char **envp)
 
     module_call_init(MODULE_INIT_QOM);
 
-    qemu_init_auxval(envp);
     qemu_cache_utils_init();
 
     if ((envlist = envlist_create()) == NULL) {