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/net/au1000_eth.c b/drivers/net/au1000_eth.c
index 185f98e..504b7ce 100644
--- a/drivers/net/au1000_eth.c
+++ b/drivers/net/au1000_eth.c
@@ -542,7 +542,7 @@
 static int num_ifs;
 
 /*
- * Setup the base address and interupt of the Au1xxx ethernet macs
+ * Setup the base address and interrupt of the Au1xxx ethernet macs
  * based on cpu type and whether the interface is enabled in sys_pinfunc
  * register. The last interface is enabled if SYS_PF_NI2 (bit 4) is 0.
  */