GAP: Reset cont_offset in start frame of SDP

If cont_offset of ccb is not reset in start frame, it's
appending previous SDP service search offset also to
current offset. Service search goes in a loop and
leads to crash on array index out of bounds.

Bug: 19810285
Change-Id: Ifee174555593f4df669977b74ce3725c75c9b426
1 file changed