qcacld-3.0: Remove sir_unpack_beacon_ie() prototype

Change I120a29c21407f82aab2c6fcdcaf1095518cb71b5 ("qcacld-3.0:
Security enhancement fixes for RSNE frame parser") removed the
implementation of sir_unpack_beacon_ie() but left the prototype. Since
the prototype is obsolete, remove it.

Change-Id: Id9d0f766b0dc3137f7012543d883791a69d10111
CRs-Fixed: 2376927
1 file changed