power: supply: qpnp-qg: Fix some error logs

When battery_id is set to a value for which there exists no
battery profile, QG driver prints error logs frequently as
some properties doesn't exist.

[ 4305.969087] QG-K: qg_get_charge_counter: Failed to get FCC for charge-counter rc=-19
[ 4305.969123] QG-K: qg_iio_read_raw: Couldn't read IIO channel 73, rc = -19
[ 4305.976657] QG-K: qg_iio_read_raw: Couldn't read IIO channel 83, rc = -19
[ 4305.989355] QG-K: qg_iio_read_raw: Couldn't read IIO channel 84, rc = -19

Fix this by changing pr_err() to pr_err_ratelimited(). While at
it, change a pr_err() to pr_debug(). Also fix an error log to
correct that the error is for reading IIO channel and not for a
property.

Change-Id: I936409d4ffafd664c571976d17ec4baf1b8de218
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>