fs/binfmt_elf.c: delete stale comment

"passed_fileno" variable was deleted 11 years ago in 2.6.25.

Link: http://lkml.kernel.org/r/20190529201747.GA23248@avx2
Fixes: d20894a2 ("Remove a.out interpreter support in ELF loader")
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/binfmt_elf.c

@@ -1127,7 +1127,6 @@ static int load_elf_binary(struct linux_binprm *bprm)
 			  load_addr, interp_load_addr);
 	if (retval < 0)
 		goto out;
-	/* N.B. passed_fileno might not be initialized? */
 	current->mm->end_code = end_code;
 	current->mm->start_code = start_code;
 	current->mm->start_data = start_data;