qcacld-3.0: Remove FEATURE_STATICALLY_ADD_11P_CHANNELS

FEATURE_STATICALLY_ADD_11P_CHANNELS was a temporary solution for
builds that were not defining DSRC channels in db.txt. That
restriction no more holds true. Also correct the list of DSRC
channels in function cds_is_dsrc_channel.

Change-Id: I1146ec9702a8eec801b635a276e981962dd42817
CRs-Fixed: 856727