Add BCTV3/PCI entry.

Rename functions bctv_* to bctv2_* and macros BCTV_* to BCTV2_* for
coexistance of BCTV2 and BCTV3.

Rename CARD_IO_GV to CARD_TO_BCTV2.

Add auto recognition of BCTV3/PCI.

PR: i386/43879
Submitted by: MOROHOSHI Akihiko <moro@remus.dti.ne.jp>
Approved by: roger
MFC after: 6 days