hw/arm/armsse: Wire up clocks

hw/arm/armsse: Wire up clocks

Create two input clocks on the ARMSSE devices, one for the normal
MAINCLK, and one for the 32KHz S32KCLK, and wire these up to the
appropriate devices.  The old property-based clock frequency setting
will remain in place until conversion is complete.

This is a migration compatibility break for machines mps2-an505,
mps2-an521, musca-a, musca-b1.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210128114145.20536-12-peter.maydell@linaro.org
Message-id: 20210121190622.22000-12-peter.maydell@linaro.org