[rilmodem] Nw selection mem leak fix

Signed-off-by: Tommi Kenakkala <tommi.kenakkala@oss.tieto.com>
[rilmodem] Call fwd mem leak fix

Signed-off-by: Tommi Kenakkala <tommi.kenakkala@oss.tieto.com>
Merge pull request #248 from tkenakka/leakfixes

Mem leak fixes