xtensa: remove arch specific early DT functions

Now that the DT core code handles bootmem arches, we can remove the xtensa
specific early_init_dt_alloc_memory_arch function. The common
early_init_dt_add_memory_arch can be used too now that xtensa switched to
memblock.

Cc: Chris Zankel <chris@zankel.net>
Cc: linux-xtensa@linux-xtensa.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>

arch/xtensa/kernel/setup.c

@@ -20,7 +20,6 @@
 #include <linux/mm.h>
 #include <linux/proc_fs.h>
 #include <linux/screen_info.h>
-#include <linux/bootmem.h>
 #include <linux/kernel.h>
 #include <linux/percpu.h>
 #include <linux/cpu.h>
@@ -218,17 +217,6 @@ static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
 }
 #endif
 
-void __init early_init_dt_add_memory_arch(u64 base, u64 size)
-{
-	size &= PAGE_MASK;
-	memblock_add(base, size);
-}
-
-void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
-{
-	return __alloc_bootmem(size, align, 0);
-}
-
 void __init early_init_devtree(void *params)
 {
 	early_init_dt_scan(params);