Memory hotplug: Move alternative function definitions to header

Move the definitions of offline_pages() and remove_memory()
for CONFIG_MEMORY_HOTREMOVE to memory_hotplug.h, where they belong,
and make them static inline.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 00569fb..dd38e62 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -234,6 +234,8 @@
 
 extern int is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
 extern void try_offline_node(int nid);
+extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
+extern void remove_memory(int nid, u64 start, u64 size);
 
 #else
 static inline int is_mem_section_removable(unsigned long pfn,
@@ -243,6 +245,13 @@
 }
 
 static inline void try_offline_node(int nid) {}
+
+static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
+{
+	return -EINVAL;
+}
+
+static inline void remove_memory(int nid, u64 start, u64 size) {}
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
 extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,