drm/etnaviv: add hwdb entry for gc400 found in STM32

The information was taken from STM32 glacore driver hw database.
The entry is named as gc7000nano_0x4652.

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>