audiod: Avoid uninitialized memory access.

audiod: Avoid uninitialized memory access.

In handle_connect(), the local pointer variable errctx is not
initialized. If an error occurs early in the function, for example
because recv_cred_buffer() fails, we jump to the "out" label and try
to print the string errctx points to. This will cause a segfault or
worse, so make sure the variable is always initialized.

This bug was found by the static analyzer of clang.