x86, numa: Avoid compiling NUMA emulation functions without CONFIG_NUMA_EMU

Both acpi_get_nodes() and amd_get_nodes() are only necessary when
CONFIG_NUMA_EMU is enabled, so avoid compiling them when the option is
disabled.

Signed-off-by: David Rientjes <rientjes@google.com>
LKML-Reference: <alpine.DEB.2.00.1012221701210.3701@chino.kir.corp.google.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index 55d106b..b326fa9 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -188,14 +188,17 @@
 extern int acpi_get_nodes(struct bootnode *physnodes);
 extern int acpi_scan_nodes(unsigned long start, unsigned long end);
 #define NR_NODE_MEMBLKS (MAX_NUMNODES*2)
+
+#ifdef CONFIG_NUMA_EMU
 extern void acpi_fake_nodes(const struct bootnode *fake_nodes,
 				   int num_nodes);
+#endif
 #else
 static inline void acpi_fake_nodes(const struct bootnode *fake_nodes,
 				   int num_nodes)
 {
 }
-#endif
+#endif /* CONFIG_ACPI_NUMA */
 
 #define acpi_unlazy_tlb(x)	leave_mm(x)