Create a root directory for debugfs at
/sys/kernel/debug/KBUILD_MODNAME_qdf/. The module name,
KBUILD_MODNAME, is used in the path to avoid conflict in case of
multiple instances of the same driver.
Any sub module in QDF can use this as the root directory to add
further files of directories. While unloading the driver the exit
routine does a recursive cleanup of any remaining files or
sub directories.
Even though debugfs is a Linux specific feature, a logic which is
related to file system for debugging can be added here.
This feature is protected with a compilation flag WLAN_DEBUGFS.
Change-Id: I21cae38b69f45c22121dfe70fe84f02423a26020
CRs-Fixed: 1083771
