soc: fsl: cpm1: qmc: Handle RPACK initialization

soc: fsl: cpm1: qmc: Handle RPACK initialization

Current code handles the CPM1 version of QMC, RPACK does not need to
be initialized. This is not the case in the QUICC Engine (QE) version.

In preparation of the support for QE, initialize the RPACK register
when the receiver is initialized and each time it is restarted.

This additional RPACK initialization has no impact in the CPM1 version
of QMC.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/20240808071132.149251-30-herve.codina@bootlin.com
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>