debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem.

Many developers use "/debug/" or "/debugfs/" or "/sys/kernel/debug/"
directory name to mount debugfs filesystem for ftrace according to
./Documentation/tracers/ftrace.txt file.

And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
existed in kernel source like ftrace, DRM, Wireless, Documentation,
Network[sky2]files to mount debugfs filesystem.

debugfs means debug filesystem for debugging easy to use by greg kroah
hartman. "/sys/kernel/debug/" name is suitable as directory name
of debugfs filesystem.
- debugfs related reference: http://lwn.net/Articles/334546/

Fix inconsistency of directory name to mount debugfs filesystem.

* From Steven Rostedt
  - find_debugfs() and tracing_files() in this patch.

Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
Acked-by     : Inaky Perez-Gonzalez <inaky@linux.intel.com>
Reviewed-by  : Steven Rostedt <rostedt@goodmis.org>
Reviewed-by  : James Smart <james.smart@emulex.com>
CC: Jiri Kosina <trivial@kernel.org>
CC: David Airlie <airlied@linux.ie>
CC: Peter Osterlund <petero2@telia.com>
CC: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
CC: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
CC: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/net/Kconfig

@@ -2206,7 +2206,7 @@ config SKGE_DEBUG
        depends on SKGE && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/skge/ethX displays the state of the internal
+	 The file /sys/kernel/debug/skge/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.
@@ -2232,7 +2232,7 @@ config SKY2_DEBUG
        depends on SKY2 && DEBUG_FS
        help
 	 This option adds the ability to dump driver state for debugging.
-	 The file debugfs/sky2/ethX displays the state of the internal
+	 The file /sys/kernel/debug/sky2/ethX displays the state of the internal
 	 transmit and receive rings.
 
 	 If unsure, say N.