typo fixes: mecanism -> mechanism

Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/include/linux/fb.h b/include/linux/fb.h
index b45928f..ffefeee 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -557,7 +557,7 @@
  * Frame buffer operations
  *
  * LOCKING NOTE: those functions must _ALL_ be called with the console
- * semaphore held, this is the only suitable locking mecanism we have
+ * semaphore held, this is the only suitable locking mechanism we have
  * in 2.6. Some may be called at interrupt time at this point though.
  */