Fix the Alva driver's check for an EL12 (as opposed to a BC640). (pl)


git-svn-id: svn://mielke.cc/main/brltty@7943 91a5dbb7-01b9-0310-9b5f-b28072856b6e
Rearrange the Alva driver code so that the key table fields only need to be assigned once. (dm)


git-svn-id: svn://mielke.cc/main/brltty@7944 91a5dbb7-01b9-0310-9b5f-b28072856b6e
Document that the Alva Easy Link 12 is now supported. (dm)


git-svn-id: svn://mielke.cc/main/brltty@7945 91a5dbb7-01b9-0310-9b5f-b28072856b6e