configs: colibri_imx7: enable CAAM driver

configs: colibri_imx7: enable CAAM driver

Access to CAAM in non-secure mode must be enabled by the boot
loader first. The U-Boot CAAM driver enables access to CAAM in
non-secure mode by default. Hence enable the CAAM driver to
allow Linux accessing CAAM directly. This prevents error
messages like the following on Linux boot:
  caam 30900000.caam: Entropy delay = 3200
  caam 30900000.caam: failed to acquire DECO 0
  caam 30900000.caam: failed to instantiate RNG

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
Acked-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>