move remaining help text from include/usage.src.h

Signed-off-by: Pere Orga <gotrunks@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

util-linux/pivot_root.c

@@ -8,6 +8,13 @@
  *
  * Licensed under GPLv2, see file LICENSE in this source tree.
  */
+
+//usage:#define pivot_root_trivial_usage
+//usage:       "NEW_ROOT PUT_OLD"
+//usage:#define pivot_root_full_usage "\n\n"
+//usage:       "Move the current root file system to PUT_OLD and make NEW_ROOT\n"
+//usage:       "the new root file system"
+
 #include "libbb.h"
 
 extern int pivot_root(const char * new_root,const char * put_old);