comedi: remove redundant assignment to variable range

The variable range is being initialized with a value that is never
read, it is being re-assigned later on. The initialization is
redundant and can be removed.

Cleans up clang scan build warning:
drivers/comedi/drivers/das08.c:180:2: warning: Value stored
to 'range' is never read [deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20240205180436.1841706-1-colin.i.king@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/comedi/drivers/das08.c

@@ -177,7 +177,6 @@ static int das08_ai_insn_read(struct comedi_device *dev,
 	int ret;
 
 	chan = CR_CHAN(insn->chanspec);
-	range = CR_RANGE(insn->chanspec);
 
 	/* clear crap */
 	inb(dev->iobase + DAS08_AI_LSB_REG);