powerpc/32: Curb objtool unannotated intra-function call warning

objtool throws the following warning:
arch/powerpc/kexec/relocate_32.o: warning: objtool: .text+0x2bc: unannotated intra-function call

Fix this warning by annotating intra-function call, using
ANNOTATE_INTRA_FUNCTION_CALL macro, to indicate that the branch target
is valid.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20221215115258.80810-1-sv@linux.ibm.com

powerpc: Remove CONFIG_FSL_BOOKE

PPC_85xx is PPC32 only.
PPC_85xx always selects E500 and is the only PPC32 that
selects E500.
FSL_BOOKE is selected when E500 and PPC32 are selected.

So FSL_BOOKE is redundant with PPC_85xx.

Remove FSL_BOOKE.

And rename four files accordingly.

cpu_setup_fsl_booke.S is not renamed because it is linked to
PPC_FSL_BOOK3E and not to FSL_BOOKE as suggested by its name.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/08e3e15594e66d63b9e89c5b4f9c35153913c28f.1663606875.git.christophe.leroy@csgroup.eu

powerpc: Avoid link stack corruption in misc asm functions

bl;mflr is used at several places to get code position.

Use bcl 20,31,+4 instead of bl in order to preserve link stack.

See commit c974809a26a1 ("powerpc/vdso: Avoid link stack corruption
in __get_datapage()") for details.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c6eabb4fb6c156f75d56dcbcc6f243e5ac0fba42.1629791763.git.christophe.leroy@csgroup.eu

powerpc/kexec: Move kexec files into a dedicated subdir.

arch/powerpc/kernel/ contains 8 files dedicated to kexec.

Move them into a dedicated subdirectory.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Move to a/p/kexec, drop the 'machine' naming and use 'core' instead]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/afbef97ec6a978574a5cf91a4441000e0a9da42a.1572351221.git.christophe.leroy@c-s.fr