qcacld-3.0: Remove MAX_NUM_LEGACY_BSSID_PER_CHANNEL macro
Change I98c1caac415ca90a1101b64e49b0909b46d42616 ("qcacld-3.0: Remove
obsolete member variables of tAniSirLim") removed the only reference
to macro MAX_NUM_LEGACY_BSSID_PER_CHANNEL. Since this macro is now
unused, remove it.
Change-Id: I2ae846a1fe7dd4b8a0905e4babfc761f67dc5545
CRs-Fixed: 2370026