Change "useing" -> "using".

Signed-off-by: NDmitri Vorobiev <dmitri.vorobiev@movial.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

include/linux/workqueue.h

@@ -94,7 +94,7 @@ struct execute_work {
 /*
  * initialize all of a work item in one go
  *
- * NOTE! No point in using "atomic_long_set()": useing a direct
+ * NOTE! No point in using "atomic_long_set()": using a direct
  * assignment of the work data initializer allows the compiler
  * to generate better code.
  */