agxv: fix deqp errors from physical device creation and fd leaks

This fixes failing dEQP-VK.api.device_init.create_instance_device_intentional_alloc_fail.basic.

In addition, agxv_physical_device_try_create handles all errors, queries the render dev id using the drm device path and call agx_close_device in failure paths.

agxv_physical_device_destroy also calls agx_close_device now, meaning that the physical device fd is not leaked.