PM/Hibernate: Move memory shrinking to snapshot.c (rev. 2)

A future patch is going to modify the memory shrinking code so that
it will make memory allocations to free memory instead of using an
artificial memory shrinking mechanism for that.  For this purpose it
is convenient to move swsusp_shrink_memory() from
kernel/power/swsusp.c to kernel/power/snapshot.c, because the new
memory-shrinking code is going to use things that are local to
kernel/power/snapshot.c .

[rev. 2: Make some functions static and remove their headers from
 kernel/power/power.h]

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 46b5ec7..ec4dbdf 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -74,7 +74,7 @@
 
 extern int create_basic_memory_bitmaps(void);
 extern void free_basic_memory_bitmaps(void);
-extern unsigned int count_data_pages(void);
+extern int swsusp_shrink_memory(void);
 
 /**
  *	Auxiliary structure used for reading the snapshot image data and
@@ -149,7 +149,6 @@
 
 /* kernel/power/disk.c */
 extern int swsusp_check(void);
-extern int swsusp_shrink_memory(void);
 extern void swsusp_free(void);
 extern int swsusp_read(unsigned int *flags_p);
 extern int swsusp_write(unsigned int flags);
@@ -176,7 +175,6 @@
 #endif
 
 #ifdef CONFIG_HIGHMEM
-unsigned int count_highmem_pages(void);
 int restore_highmem(void);
 #else
 static inline unsigned int count_highmem_pages(void) { return 0; }