[S390] disassembler: fix b2 opcodes like srst, bsg, and others

[S390] disassembler: fix b2 opcodes like srst, bsg, and others

The instruction table for b2 opcodes was missing an opfrag value
for the cpya instruction. All instructions specified after cpya
were not considered by the disassembler. The fix is simple and
obvious - add the opfrag field to the cpya instruction.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>