Remove a compile warning.

diff -urpNX dontdiff linus-2.5/fs/binfmt_elf.c parisc-2.5/fs/binfmt_elf.c
--- linus-2.5/fs/binfmt_elf.c	Thu Jul 10 16:18:33 2003
+++ parisc-2.5/fs/binfmt_elf.c	Wed Jul  2 16:01:11 2003
@@ -114,7 +114,7 @@ static void padzero(unsigned long elf_bs
 #define STACK_ADD(sp, items) ((elf_addr_t *)(sp) + (items))
 #define STACK_ROUND(sp, items) \
 	((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
-#define STACK_ALLOC(sp, len) ({ elf_addr_t *old_sp = sp; sp += len; old_sp; })
+#define STACK_ALLOC(sp, len) ({ elf_addr_t *old_sp = (elf_addr_t *)sp; sp += len; old_sp; })
 #else
 #define STACK_ADD(sp, items) ((elf_addr_t *)(sp) - (items))
 #define STACK_ROUND(sp, items) \