treewide: Fix typos in various parts of the kernel, and fix some comments.

The below patch fixes some typos in various parts of the kernel, as well as fixes some comments.
Please let me know if I missed anything, and I will try to get it changed and resent.

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 1f9e951..e8acca89 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -820,7 +820,7 @@
 	 * Specifically, the timestamp in @vblank_time should correspond as
 	 * closely as possible to the time when the first video scanline of
 	 * the video frame after the end of VBLANK will start scanning out,
-	 * the time immmediately after end of the VBLANK interval. If the
+	 * the time immediately after end of the VBLANK interval. If the
 	 * @crtc is currently inside VBLANK, this will be a time in the future.
 	 * If the @crtc is currently scanning out a frame, this will be the
 	 * past start time of the current scanout. This is meant to adhere
diff --git a/include/linux/wanrouter.h b/include/linux/wanrouter.h
index e0aa396..3157cc1 100644
--- a/include/linux/wanrouter.h
+++ b/include/linux/wanrouter.h
@@ -309,7 +309,7 @@
 #define WANOPT_EVEN	2
 
 /* CHDLC Protocol Options */
-/* DF Commmented out for now.
+/* DF Commented out for now.
 
 #define WANOPT_CHDLC_NO_DCD		IGNORE_DCD_FOR_LINK_STAT
 #define WANOPT_CHDLC_NO_CTS		IGNORE_CTS_FOR_LINK_STAT
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 72eddd1..bd3487d 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1423,7 +1423,7 @@
  * DOC: Beacon filter support
  *
  * Some hardware have beacon filter support to reduce host cpu wakeups
- * which will reduce system power consumption. It usuallly works so that
+ * which will reduce system power consumption. It usually works so that
  * the firmware creates a checksum of the beacon but omits all constantly
  * changing elements (TSF, TIM etc). Whenever the checksum changes the
  * beacon is forwarded to the host, otherwise it will be just dropped. That