Fix spelling of 'platform' in comments and doc

Replace platfrom -> platform.

This is a frequent spelling bug.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/include/linux/dm9000.h b/include/linux/dm9000.h
index c30879c..96e8769 100644
--- a/include/linux/dm9000.h
+++ b/include/linux/dm9000.h
@@ -23,7 +23,7 @@
 #define DM9000_PLATF_NO_EEPROM	(0x0010)
 #define DM9000_PLATF_SIMPLE_PHY (0x0020)  /* Use NSR to find LinkStatus */
 
-/* platfrom data for platfrom device structure's platfrom_data field */
+/* platform data for platform device structure's platform_data field */
 
 struct dm9000_plat_data {
 	unsigned int	flags;