Changes

gsm48_cc_tx_setup: remove extra bearer_cap var

Store the bearer capabilities directly in the transaction, instead of
storing them in a separate variable first, then copying it to the
transaction, then using both the separate variable and the copy in the
transaction later on. The extra variable is not needed and only makes it
more compilicated.

Add an explicit '.transfer = GSM48_BCAP_ITCAP_SPEECH,' while at it in
the speech case. This was already set implicitly because
GSM48_BCAP_ITCAP_SPEECH is 0.

Change-Id: I247ef10923c2875ca75e73046f4b8ed14190d4d2