staging/vt6656: Fix sparse warning constant 0xffffffff00000000U is so big it is unsig...

staging/vt6656: Fix sparse warning constant 0xffffffff00000000U is so big it is unsigned long

Since 64a101b0c12b86378d4a6e04fc58316ccfa2be65
'staging: vt6656: Remove QWORD from source and replace with u64.'
a new sparse warning showed up:

'drivers/staging/vt6656/card.c:798:26: sparse: constant
 0xffffffff00000000U is so big it is unsigned long'

-> Append L to fix the warning.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Cc: Forest Bond <forest@alittletooquiet.net>
Cc: Malcolm Priestley <tvboxspy@gmail.com>
Cc: "Justin P. Mattock" <justinmattock@gmail.com>
Cc: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>