memory-hotplug: create /sys/firmware/memmap entry for new memory

A memmap is a directory in sysfs which includes 3 text files: start, end
and type.  For example:

start: 	0x100000
end:	0x7e7b1cff
type:	System RAM

Interface firmware_map_add was not called explicitly.  Remove it and add
function firmware_map_add_hotplug as hotplug interface of memmap.

Each memory entry has a memmap in sysfs, When we hot-add new memory, sysfs
does not export memmap entry for it.  We add a call in function add_memory
to function firmware_map_add_hotplug.

Add a new function add_sysfs_fw_map_entry() to create memmap entry, it
will be called when initialize memmap and hot-add memory.

[akpm@linux-foundation.org: un-kernedoc a no longer kerneldoc comment]
Signed-off-by: Shaohui Zheng <shaohui.zheng@intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/firmware-map.h b/include/linux/firmware-map.h
index 875451f..c6dcc1d 100644
--- a/include/linux/firmware-map.h
+++ b/include/linux/firmware-map.h
@@ -24,17 +24,17 @@
  */
 #ifdef CONFIG_FIRMWARE_MEMMAP
 
-int firmware_map_add(u64 start, u64 end, const char *type);
 int firmware_map_add_early(u64 start, u64 end, const char *type);
+int firmware_map_add_hotplug(u64 start, u64 end, const char *type);
 
 #else /* CONFIG_FIRMWARE_MEMMAP */
 
-static inline int firmware_map_add(u64 start, u64 end, const char *type)
+static inline int firmware_map_add_early(u64 start, u64 end, const char *type)
 {
 	return 0;
 }
 
-static inline int firmware_map_add_early(u64 start, u64 end, const char *type)
+static inline int firmware_map_add_hotplug(u64 start, u64 end, const char *type)
 {
 	return 0;
 }