powerpc/booke: Disable STRICT_KERNEL_RWX, DEBUG_PAGEALLOC and KFENCE

fsl_booke and 44x are not able to map kernel linear memory with
pages, so they can't support DEBUG_PAGEALLOC and KFENCE, and
STRICT_KERNEL_RWX is also a problem for now.

Enable those only on book3s (both 32 and 64 except KFENCE), 8xx and 40x.

Fixes: 88df6e90 ("[POWERPC] DEBUG_PAGEALLOC for 32-bit")
Fixes: 95902e6c ("powerpc/mm: Implement STRICT_KERNEL_RWX on PPC32")
Fixes: 90cbac0e

 ("powerpc: Enable KFENCE for PPC32")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d1ad9fdd9b27da3fdfa16510bb542ed51fa6e134.1634292136.git.christophe.leroy@csgroup.eu