drm/omap: dss: venc: convert to devm_drm_bridge_alloc() API

drm/omap: dss: venc: convert to devm_drm_bridge_alloc() API

This is the new API for allocating DRM bridges.

Switching from a non-devm to a devm allocation allows removing the kfree()
in the remove function and in the probe error management code, and as a
consequence to simplify the code flow by removing now unnecessary gotos.

Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250509-drm-bridge-convert-to-alloc-api-v3-13-b8bc1f16d7aa@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>