pci: Move inline PCI functions to pci_ops.h

Move inline function where they belong to. Fixes compilation
on non x86 platforms.

Change-Id: Ia05391c43b8d501bd68df5654bcfb587f8786f71
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/25720
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/intel/skylake/systemagent.c

@@ -20,6 +20,7 @@
 #include <console/console.h>
 #include <delay.h>
 #include <device/device.h>
+#include <device/pci_ops.h>
 #include <intelblocks/systemagent.h>
 #include <soc/cpu.h>
 #include <soc/iomap.h>