FDPIC: For-loop in elf_core_vma_data_size() is incorrect

Fix an incorrect for-loop in elf_core_vma_data_size().  The advance-pointer
statement lacks an assignment:

	  CC      fs/binfmt_elf_fdpic.o
	fs/binfmt_elf_fdpic.c: In function 'elf_core_vma_data_size':
	fs/binfmt_elf_fdpic.c:1593: warning: statement with no effect
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/binfmt_elf_fdpic.c

@@ -1590,7 +1590,7 @@ static size_t elf_core_vma_data_size(unsigned long mm_flags)
 	struct vm_area_struct *vma;
 	size_t size = 0;
 
-	for (vma = current->mm->mmap; vma; vma->vm_next)
+	for (vma = current->mm->mmap; vma; vma = vma->vm_next)
 		if (maydump(vma, mm_flags))
 			size += vma->vm_end - vma->vm_start;
 	return size;