microblaze: Cleanup unused functions

These functions haven't been used, so just remove them. The patch
just uses grep to verify.
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>
Reviewed-by: NAnup Patel <anup@brainfault.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NPalmer Dabbelt <palmerdabbelt@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Simek <monstr@monstr.eu>
Link: https://lore.kernel.org/r/1622350408-44875-3-git-send-email-guoren@kernel.orgSigned-off-by: NMichal Simek <michal.simek@xilinx.com>

arch/microblaze/include/asm/page.h

@@ -35,9 +35,6 @@
 
 #define ARCH_SLAB_MINALIGN	L1_CACHE_BYTES
 
-#define PAGE_UP(addr)	(((addr)+((PAGE_SIZE)-1))&(~((PAGE_SIZE)-1)))
-#define PAGE_DOWN(addr)	((addr)&(~((PAGE_SIZE)-1)))
-
 /*
  * PAGE_OFFSET -- the first address of the first page of memory. With MMU
  * it is set to the kernel start address (aligned on a page boundary).