xen/acpi: move xen_acpi_get_pxm under CONFIG_XEN_DOM0
xen/acpi: move xen_acpi_get_pxm under CONFIG_XEN_DOM0

To avoid compile issue and it's meanigfull only under CONFIG_XEN_DOM0.

In file included from linux/arch/x86/xen/enlighten.c:47:0:
	linux/include/xen/acpi.h:75:76: error: unknown type name ‘acpi_handle’
make[3]: *** [arch/x86/xen/enlighten.o] Error 1

Signed-off-by: Liu Jinsong <24f93389b1a33ace4517ce0414ae81efc3379829@intel.com>
[v1: Fixed spelling mistakes]
Signed-off-by: Konrad Rzeszutek Wilk <da3a51b335cef0eb0e2c329c5ef6bcd6acef687a@oracle.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs