qtest: Add functions for accessing devices on Aspeed I2C controller

Add read and write functions for accessing registers of I2C devices
connected to the Aspeed I2C controller.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Ninad Palsule <ninad@linux.ibm.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-id: 20230331173051.3857801-2-stefanb@linux.ibm.com
3 files changed