soc: microchip: mec5: Disable PM in mec174x, mec175x, and mech172x

We disable power management by removing select HAS_PM. At this time
these new SoC do not have any power management code. With HAS_PM
selected the zephyr test runner will choose PM tests which fail to
build.  PM support will be enabled in the future once we decide
which of the many Zephyr PM implementations we will support.

Signed-off-by: Scott Worley <scott.worley@microchip.com>