* gregset.h: New file. Typedefs for gdb_gregset_t and
gdb_fpregset_t, prototypes for supply_gregset and friends.
* procfs.c: Include gregset.h. Delete local prototypes for
supply_gregset etc., and local typedef gdb_gregset_t etc.
* sol-thread.c: Include gregset.h, delete local prototypes,
add appropriate casts to gdb_gregset_t.
* uw-thread.c, lin-thread.c, core-sol2.c, core-regset.c,
sparc-tdep.c, ptx4-nat.c, ppc-linux-nat.c, mipsv4-nat.c,
m88k-nat.c, m68klinux-nat.c, m68k-tdep.c, irix5-nat.c,
irix4-nat.c, ia64-linux-nat.c, i386v4-nat.c, cxux-nat.c,
arm-linux-nat.c, alpha-nat.c: Include gregset.h.
* config/nm-linux.h: Define GDB_GREGSET_T, GDB_FPREGET_T.
* config/sparc/tm-sun4sol2.h: Ditto.
* gdbarch.sh: Add FP0_REGNUM to list of multi-arched register numbers.
* gdbarch.c, gdbarch.h: Regenerate.
* core-regset.c: Change FP0_REGNUM to a runtime test.
* procfs.c: Ditto.
* sun3-nat.c: Ditto.
* sparc-tdep.c: Ditto.
* i386mach-nat.c: Remove unnecessary ifdef for FP0_REGNUM.
* ptx4-nat.c: Ditto.
* sol-thread.c (sol_thread_create_inferior): only add the thread
to the thread list if it is not already in there.
(prototypes for thread_db func ptrs): pretty up formatting.
