Fix misspellings of "system", "controller", "interrupt" and "necessary".

Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
diff --git a/drivers/char/rocket.c b/drivers/char/rocket.c
index 7e6a3a4..d83419c 100644
--- a/drivers/char/rocket.c
+++ b/drivers/char/rocket.c
@@ -563,7 +563,7 @@
 		/*  Get a ptr to the board's control struct */
 		ctlp = sCtlNumToCtlPtr(ctrl);
 
-		/*  Get the interupt status from the board */
+		/*  Get the interrupt status from the board */
 #ifdef CONFIG_PCI
 		if (ctlp->BusType == isPCI)
 			CtlMask = sPCIGetControllerIntStatus(ctlp);