powerpc/kernel: Fix ppc_save_regs inclusion in build

Recent patch fixed an old commit
'fc2a5a6161a2 ("powerpc/64s: ppc_save_regs is now needed for all 64s builds")'
which is to include building of ppc_save_reg.c only when XMON
and KEXEC_CORE and PPC_BOOK3S are enabled. This was valid, since
ppc_save_regs was called only in replay_system_reset() of old
irq.c which was under BOOK3S.

But there has been multiple refactoring of irq.c and have
added call to ppc_save_regs() from __replay_soft_interrupts
-> replay_soft_interrupts which is part of irq_64.c included
under CONFIG_PPC64. And since ppc_save_regs is called in
CRASH_DUMP path as part of crash_setup_regs in kexec.h,
CONFIG_PPC32 also needs it.

So with this recent patch which enabled the building of
ppc_save_regs.c caused a build break when none of these
(XMON, KEXEC_CORE, BOOK3S) where enabled as part of config.
Patch to enable building of ppc_save_regs.c by defaults.

Signed-off-by: Madhavan Srinivasan <[email protected]>
Link: https://patch.msgid.link/[email protected]

Author: maddy-kerneldev

arch/powerpc/kernel/Makefile

@@ -160,9 +160,7 @@ endif
 
 obj64-$(CONFIG_PPC_TRANSACTIONAL_MEM)	+= tm.o
 
-ifneq ($(CONFIG_XMON)$(CONFIG_KEXEC_CORE)$(CONFIG_PPC_BOOK3S),)
 obj-y				+= ppc_save_regs.o
-endif
 
 obj-$(CONFIG_EPAPR_PARAVIRT)	+= epapr_paravirt.o epapr_hcalls.o
 obj-$(CONFIG_KVM_GUEST)		+= kvm.o kvm_emul.o