library: uptime API changes

Removed the printf_uptime, binaries can do printf easily enough.
sprint_uptime split into two as there wasn't a lot of common
code
 sprint_uptime(): old style uptime line
 sprint_uptime_short(): short new style "uptime -p"

Hertz_hack needed this, no sane system uses the code (I think)
so just assume 100 like we do in FreeBSD.

proc/uptime.h

@@ -0,0 +1,38 @@
+/*
+ * uptime - uptime related functions - part of procps
+ *
+ * Copyright (C) 1992-1998 Michael K. Johnson <johnsonm@redhat.com>
+ * Copyright (C) ???? Larry Greenfield <greenfie@gauss.rutgers.edu>
+ * Copyright (C) 1993 J. Cowley
+ * Copyright (C) 1998-2003 Albert Cahalan
+ * Copyright (C) 2015 Craig Small <csmall@enc.com.au>
+ *
+ * This library is free software; you can redistribute it and/or
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#ifndef PROC_UPTIME_H
+#define PROC_UPTIME_H
+
+#include <proc/procps.h>
+
+__BEGIN_DECLS
+
+int uptime(double *uptime_secs, double *idle_secs);
+char *sprint_uptime(void);
+char *sprint_uptime_short(void);
+
+__END_DECLS
+
+#endif