drm/amd: Fix initialization mistake for NBIO 7.3.0

drm/amd: Fix initialization mistake for NBIO 7.3.0

The same strapping initialization issue that happened on NBIO 7.5.1
appears to be happening on NBIO 7.3.0.
Apply the same fix to 7.3.0 as well.

Note: This workaround relies upon the integrated GPU being enabled
in BIOS. If the integrated GPU is disabled in BIOS a different
workaround will be required.

Reported-by: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/linux-usb/Y%2Fz9GdHjPyF2rNG3@glanzmann.de/T/#u
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>