platform/x86: intel_pmc: Make PCI dependency explicit

After commit 5d32a665 (PCI/ACPI: Allow ACPI to be built without
CONFIG_PCI set) dependencies on CONFIG_PCI that previously were
satisfied implicitly through dependencies on CONFIG_ACPI have to be
specified directly.

Some code in intel_pmc relies on PCI for execution. Specify this
in the Kconfig.

[ Andy S: For sake of a quick fix this introduces a new mandatory
  dependency to the driver which may survive without it. Otherwise
  we need to revisit the driver architecture to address this
  properly. ]

Fixes: 5d32a665 ("PCI/ACPI: Allow ACPI to be built without CONFIG_PCI set")
Signed-off-by: Sinan Kaya <okaya@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>