Move all the pseries kexec code into one file, platforms/pseries/kexec.c
Provide helpers for setting up ppc_md.kexec_cpu_down, so that we don't
have to have #ifdef CONFIG_KEXEC in setup.c

Move the initialisation of the ppc_md kexec callbacks into an init routine.
This is well and truly early enough to cause no change in behaviour, we
can't kexec until userspace has given us a kernel to kexec into.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Move some extern declarations from setup.c into the new pseries.h.
While we're at it, provide dummy implementations for !SMP, to avoid
cluttering the C file with more #ifdefs.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Following the example of platforms/pasemi, consolidate a couple of
tiny header files in platforms/pseries into pseries.h.

This gives us a convenient place to put things that need to be
available to the platform code, but not public. And hopefully will
help people resist the temptation of sticking externs in C files.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>