* config/m88k/tm-m88k.h: Update copyright.
(m88k_target_write_pc): Declare
(TARGET_WRITE_PC): Redefine using m88k_target_write_pc.
(M88K_NNPC_REGNUM): Rename NNPC_REGNUM.
(SHIFT_INST_REGS): Update definition.
* m88k-tdep.c (m88k_target_write_pc): New function. Implement
using old definition of TARGET_WRITE_PC.
* regcache.c (generic_target_write_pc): Delete code handling
NNPC_REGNUM.
* gdbarch.sh (NNPC_REGNUM): Delete.
* gdbarch.h, gdbarch.c: Regenerate.
* gdbint.texinfo (Target Architecture Definition): Delete
documentation on NNPC_REGNUM.