iwlwifi: mvm: refactor debugfs copy_from_user()

Abstract the copy_from_user() pattern into the macros defining
debugfs files, reducing the code and making adding new files
safer by avoiding having deal with copy_from_user() directly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

diff --cc drivers/net/wireless/iwlwifi/mvm/debugfs.c
Simple merge

diff --cc drivers/net/wireless/iwlwifi/mvm/debugfs.h
Simple merge