ALSA: line6: Remove revision.h

The definition is no longer used.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/usb/line6/driver.c

@@ -22,7 +22,6 @@
 #include "driver.h"
 #include "midi.h"
 #include "playback.h"
-#include "revision.h"
 #include "usbdefs.h"
 
 #define DRIVER_AUTHOR  "Markus Grabner <grabner@icg.tugraz.at>"

sound/usb/line6/revision.h

-#ifndef DRIVER_REVISION
-/* current subversion revision */
-#define DRIVER_REVISION " (904)"
-#endif