package/freescale-imx/firmware-imx: bump version to 8.9

This version is aligned with 5.4.47_2.2.0 NXP Linux BSP.

Signed-off-by: Stephane Viau <stephane.viau@oss.nxp.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>