spelling: s/retreive/retrieve/

Signed-off-by: Adrian Bunk <bunk@stusta.de>

drivers/message/i2o/README.ioctl

@@ -185,7 +185,7 @@ VII. Getting Parameters
       ENOMEM      Kernel memory allocation error
 
    A return value of 0 does not mean that the value was actually
-   properly retreived.  The user should check the result list 
+   properly retrieved.  The user should check the result list 
    to determine the specific status of the transaction.
 
 VIII. Downloading Software