procfs directory entry cleanup

Function proc_register() will assign proc_dir_operations and
proc_dir_inode_operations to ent's members proc_fops and proc_iops
correctly if ent is a directory. So the early assignment isn't
necessary.

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>