Spell check all source code variables, comments and strings.

LUFA/Drivers/USB/HighLevel/StdDescriptors.h

@@ -72,7 +72,7 @@
 				 *  a unique serial number internally, and setting the device descriptors serial number string index to this value
 				 *  will cause it to use the internal serial number.
 				 *
-				 *  On unsupported devices, this will evaluate to NO_DESCRIPTOR and so will force the host to create a pseduo-serial
+				 *  On unsupported devices, this will evaluate to NO_DESCRIPTOR and so will force the host to create a pseudo-serial
 				 *  number for the device.
 				 */
 				#define USE_INTERNAL_SERIAL           0xDC