GATT: Remove unhandled request info

GATT: Remove unhandled request info

[Model] All
[BinType] AP
[Customer] OPEN

[Issue#] N/A
[Request] Internal
[Occurrence Version] N/A

[Problem] Server app send response, but it is handled as invalid request info
[Cause & Measure] request info is not removed on previous link. Remove request info.
[Checking Method] n/a

[Team] Convergence BT
[Developer] Injun Yang
[Solution company] Samsung
[Change Type] Specification change

Change-Id: Id6cc4293f6ab9a89948ecda35ed481793a9f7d5a
Signed-off-by: Wootak Jung <wootak.jung@samsung.com>