iio:meter:ade7759: Removing use of deprecated macros (S_IRUGO, S_IWUSR)

This fixes the coding style issue of using (S_IWUSR | S_IRUGO) in place of
4-digit octal numbers.

Signed-off-by: Chen Guanqiao <chen.chenchacha@foxmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
1 file changed