cfg80211 debugfs: Cleanup some checkpatch issues

This fixes the checkpatch.pl warnings:
* Macros should not use a trailing semicolon.
* Spaces required around that '='.
* Symbolic permissions 'S_IRUGO' are not preferred.

Signed-off-by: Dmitriy Pichugin <smokeman85@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>