[RILMODEM] initial support to read and delete sms from sim

Signed-off-by: Jarko Poutiainen <Jarko.Poutiainen@oss.tieto.com>
[RILMODEM] change cb_data_new2 to abort in failure

Signed-off-by: Jarko Poutiainen <Jarko.Poutiainen@oss.tieto.com>
[RILMODEM] removing unnecessary empty lines and null check

Signed-off-by: Jarko Poutiainen <Jarko.Poutiainen@oss.tieto.com>
Merge pull request #235 from jpoutiai/sms-on-sim

[RILMODEM] initial support to read and delete sms from sim (class2, voicemail mwi)