s390/bitops: remove unnecessary macro definitions in asm/bitops.h

Remove unused __BITOPS_ALIGN, and replace __BITOPS_WORDSIZE with
BITS_PER_LONG.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>