debugfs: improve formatting of debugfs_real_fops()

Type of debugfs_real_fops() is longer than parameters and
the name, so there is no way to break the declaration nicely.
We have to go over 80 characters.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>