added support for wrt54g3gv2-vf and new trx header format

 - hacked addpattern due to changes in header format
 - added "-5" to addpattern, some 0xFF are needed for trx2 header
   "-4" broke CRC checking in CFE
 - hacked trx.c due to new header format version
 - added target to create trx-V2 images

the flashmap driver possibly needs to be customized.

SVN-Revision: 20433