staging: iio: ad2s1210: remove redundant assignment to variable negative

Variable negative is being assigned a value that is never read, it is
being re-assigned later. The assignment is redundant and can be removed.

Cleans up clang scan build warning:
drivers/staging/iio/resolver/ad2s1210.c:502:3: warning: Value stored
to 'negative' is never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/staging/iio/resolver/ad2s1210.c

···
 		ret = IIO_VAL_INT;
 		break;
 	case IIO_ANGL_VEL:
-		negative = st->rx[0] & 0x80;
 		vel = be16_to_cpup((__be16 *)st->rx);
 		vel >>= 16 - st->resolution;
 		if (vel & 0x8000) {