treewide: Fix typo in Documentation/DocBook

This patch fix spelling typo in Documentation/DocBook.
It is because .html and .xml files are generated by make htmldocs,
I have to fix a typo within the source files.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/net/core/dev.c b/net/core/dev.c
index d2b87db..70d2da3 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3424,7 +3424,7 @@
  *	@rx_handler: receive handler to register
  *	@rx_handler_data: data pointer that is used by rx handler
  *
- *	Register a receive hander for a device. This handler will then be
+ *	Register a receive handler for a device. This handler will then be
  *	called from __netif_receive_skb. A negative errno code is returned
  *	on a failure.
  *