soc: qcom: peripheral-loader: change log level

Reduce the log level for the return value check of
of_get_named_gpio_flags of the proxy unvote gpio.

This avoids confusion during boot up when the gpio provider
is not yet probed.

CRs-Fixed: 907816
Change-Id: I28f7cd6319ac6f1d1e31f5cd83fe592feb8bbf0b
Signed-off-by: David Keitel <dkeitel@codeaurora.org>