platform/x86/amd/pmc: Fix implicit declaration error on i386

Add depended header file to fix error on i386 due to implicit declaration
of function ‘writeq’.

Fixes: 2dc77993 ("platform/x86/amd/pmc: Add AMD MP2 STB functionality")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202404160320.QAHyZ0c3-lkp@intel.com/Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Link: https://lore.kernel.org/r/20240416025312.731809-1-Basavaraj.Natikar@amd.comSigned-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/x86/amd/pmc/mp2_stb.c

@@ -11,6 +11,7 @@
 #include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/io.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
 #include <linux/iopoll.h>
 #include <linux/pci.h>
 #include <linux/sizes.h>