libmsc/gsm_04_80.c: make the API abstract from ss_request struct
There is no need to pass a pointer to a ss_request struct when
calling the gsm0480_send_ussd_* functions, because they only
use both transaction ID and InvokeID from there, which may
be passed directly.
This change allows one to use this API without parsing the
whole GSM 04.80 message, or when parsing is failed. Moreover,
if InvokeID is not available, one can pass any incorrect,
(e.g. negative) value, so the universal NULL tag will be used.
Finally, setting a TI flag is also up to the caller.
Change-Id: I13d5abbfdcf8238ebaf0566c420f09cd9255b648
3 files changed