Fixed leaking of global references in JNI LLCP socket implementation

Global JNI references are created via call to nfc_jni_cache_object() in
numerous places at the time of LLCP socket create and LLCP socket
accept.
These global references were never deleted when no longer needed. Which
caused a global reference leak each time NFC setting was disabled/enabled
and for each P2P (Beam) transaction.

Change-Id: I8482aff269c519cede85e631c38b7f8f01b52aeb
Orig-Change-Id: I03465982bec100d2bd1644c7728c64edefa4dfde
Signed-off-by: Sebastien Griffoul <sebastien.griffoul@intel.com>
Signed-off-by: Xiaokang Qin <xiaokang.qin@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
Signed-off-by: Jack Ren <jack.ren@intel.com>
Signed-off-by: Dejan REBRACA <dejanx.rebraca@intel.com>
Signed-off-by: Jian Luo <jian.luo@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
Signed-off-by: Jack Ren <jack.ren@intel.com>
Author-tracking-BZ: 43260