alpha: use bcd2bin/bin2bcd

Change alpha to use the new bcd2bin/bin2bcd functions instead of the
obsolete BCD_TO_BIN/BIN_TO_BCD macros.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>