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/ide/pci/it821x.c b/drivers/ide/pci/it821x.c
index ec45b72..08e820e 100644
--- a/drivers/ide/pci/it821x.c
+++ b/drivers/ide/pci/it821x.c
@@ -95,7 +95,7 @@
 
 /*
  *	We allow users to force the card into non raid mode without
- *	flashing the alternative BIOS. This is also neccessary right now
+ *	flashing the alternative BIOS. This is also necessary right now
  *	for embedded platforms that cannot run a PC BIOS but are using this
  *	device.
  */
@@ -564,7 +564,7 @@
 
 	/*
 	 *	Not in the docs but according to the reference driver
-	 *	this is neccessary.
+	 *	this is necessary.
 	 */
 
 	pci_read_config_byte(hwif->pci_dev, 0x08, &conf);