Staging: iio: meter: Add blank line after declarations

This patch adds a blank line after declarations found by checkpatch warning.

Signed-off-by: Darshana Padmadas <darshanapadmadas@gmail.com>
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>