iio: core: fix a few code style issues

* Fix indent in else statement
* Remove unnecessary 'else' after 'break'
* Remove space in '* attr'

Signed-off-by: Alexander Vorwerk <alexander.vorwerk@stud.uni-goettingen.de>
Link: https://lore.kernel.org/r/20220312180343.8935-1-alexander.vorwerk@stud.uni-goettingen.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/industrialio-core.c

@@ -892,7 +892,6 @@ static int __iio_str_to_fixpoint(const char *str, int fract_mult,
 		} else if (*str == '\n') {
 			if (*(str + 1) == '\0')
 				break;
-			else
 			return -EINVAL;
 		} else if (!strncmp(str, " dB", sizeof(" dB") - 1) && scale_db) {
 			/* Ignore the dB suffix */