usb: misc: onboard_usb_dev: Fix usb5744 initialization sequence

usb: misc: onboard_usb_dev: Fix usb5744 initialization sequence

Introduce i2c APIs to read/write for proper configuration register
programming. It ensures that read-modify-write sequence is performed
and reserved bit in Runtime Flags 2 register are not touched.

Also legacy smbus block write inserted an extra count value into the
i2c data stream which breaks the register write on the usb5744.

Switching to new read/write i2c APIs fixes both issues.

Fixes: 6782311d04df ("usb: misc: onboard_usb_dev: add Microchip usb5744 SMBus programming support")
Cc: stable <stable@kernel.org>
Signed-off-by: Jonathan Stroud <jonathan.stroud@amd.com>
Co-developed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://lore.kernel.org/r/1747398760-284021-1-git-send-email-radhey.shyam.pandey@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>