powerpc/64/kexec: Fix MMU cleanup on radix

Just using the hash ops won't work anymore since radix will have
NULL in there. Instead create an mmu_cleanup_all() function which
will do the right thing based on the MMU mode.

For Radix, for now I clear UPRT and the PTCR, effectively switching
back to Radix with no partition table setup.

Currently set it to NULL on BookE thought it might be a good idea
to wipe the TLB there (Scott ?)

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/machine_kexec_64.c

@@ -55,9 +55,6 @@ int default_machine_kexec_prepare(struct kimage *image)
 	const unsigned long *basep;
 	const unsigned int *sizep;
 
-	if (!mmu_hash_ops.hpte_clear_all)
-		return -ENOENT;
-
 	/*
 	 * Since we use the kernel fault handlers and paging code to
 	 * handle the virtual mode, we must make sure no destination
@@ -379,13 +376,8 @@ void default_machine_kexec(struct kimage *image)
 	 * a toc is easier in C, so pass in what we can.
 	 */
 	kexec_sequence(&kexec_stack, image->start, image,
-			page_address(image->control_code_page),
-#ifdef CONFIG_PPC_STD_MMU
-			mmu_hash_ops.hpte_clear_all
-#else
-			NULL
-#endif
-	);
+		       page_address(image->control_code_page),
+		       mmu_cleanup_all);
 	/* NOTREACHED */
 }