Long dial string support

Dial strings can now be as long as 120 digits (not counting '+'). This feature is going to be needed by the FDN feature.
An FDN may consist of a phone number plus a DTMF string. In order to have the call succeed when FDN is enabled, both parts need to be provided when making a call as a single dial string. For AT modems the long dial string can be and has to be passed as is to the modem, for ISI modems the dial string needs to be split into phone number (dest. address) and DTMF tone (post dest. address) before feeding it to the modem.

Andras Domokos (2):
common: add long dial string support isimodem/voicecall: add long dial string support

 drivers/isimodem/voicecall.c |   83 +++++++++++++++++++++++++++++++++---------
 include/types.h              |    2 +-
 src/common.c                 |   12 +++---
 3 files changed, 72 insertions(+), 25 deletions(-)