Baud definitions (B9600 for example) are again encoded; Now supports the...

Baud definitions (B9600 for example) are again encoded; Now supports the BOTHER settings which allows specifying the baud via c_ispeed and c_ospeed termios fields

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4970 42af7a65-404d-4744-a932-0658087f49c3