MLK-10524: iMX6x: Implement workaround for Cortex-A9 errata 845369

MLK-10524: iMX6x: Implement workaround for Cortex-A9 errata 845369

Under very rare timing circumstances, transitioning into streaming
mode might create a data corruption. Present on Two or more processors
or 1 core with ACP, all revisions. This erratum can be worked round
by setting bit[22] of the undocumented Diagnostic Control Register to 1.

Signed-off-by: Nitin Garg <nitin.garg@freescale.com>
(cherry picked from commit 70ad44e523680de67dd8b7a7505d7f27799980ee)
(cherry picked from commit f20a65847577ff40dc7e3739a0bb69926885c734)