phy: amlogic: meson8b-usb2: unset the IDDQ bit during PHY power-on

The vendor driver unsets the set_iddig bit during power-on as well and
sets it when suspending the PHY. I did not notice this in the vendor
driver first, because it's part of the dwc_otg driver there (instead of
their PHY code). While here, also add all other REG_DBG_UART register
bit definitions.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Thomas Graichen <thomas.graichen@gmail.com>
Link: https://lore.kernel.org/r/20200512222424.549351-6-martin.blumenstingl@googlemail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>