iio: adc: qcom-pm8xxx-xoadc: Remove useless condition in pm8xxx_xoadc_parse_channel()

The left side of the loop condition never becomes false. hwchan cannot be
NULL, because it points to elements of the hw_channels array that takes
one of 4 predefined values: pm8018_xoadc_channels, pm8038_xoadc_channels,
pm8058_xoadc_channels, pm8921_xoadc_channels.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Reviewed-by: Andi Shyti <[e-mail]>
Reviewed-by: Linus Walleij <[e-mail]>
Signed-off-by: Kasumov Ruslan <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/adc/qcom-pm8xxx-xoadc.c

···
 	/* Find the right channel setting */
 	chid = 0;
 	hwchan = &hw_channels[0];
-	while (hwchan && hwchan->datasheet_name) {
+	while (hwchan->datasheet_name) {
 		if (hwchan->pre_scale_mux == pre_scale_mux &&
 		    hwchan->amux_channel == amux_channel)
 			break;