platform/x86: intel_pmc_core: Substitute PCI with CPUID enumeration

The Only use of PCI device enumeration here is to get the PMC base address
which is a fixed value i.e. 0xFE000000. On some platforms this can be read
through a non standard PCI BAR. But after Kabylake, PMC is not exposed as a
PCI device anymore. There are other non standard methods like ACPI LPIT
which can also be used for obtaining this value.

For simplicity, this value can be hardcoded as it won't change.

Since we don't have a PMC PCI device on any platform after Kabylake, this
creates a foundation for future SoC support.

Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>