Add user suspend support

Attached patch adds use mode suspend support. Currently dracut won't resume after s2disk. There are several points that likely need discussion.

1. Command like parsing partially duplicates that of 95resume. Both are using the same parameter resume=; and I'd like to make sure each one is self contained in case other module is disabled. Alternative probably is

a) make 95uswsusp install file from 95resume under the same name
b) supply resume= parsing like some (library) file outside of these modules and make both of them install it

I do not particular care one way or other except currently dracut stops to ask me whether file should be overwritten. This will break non- interactive usage.

2. Location of resume binary may well be system dependant

3. Splashed handling is rather biased toward plymouth and how I understand it (i.e. - either splash everywhere or nowhere).

Comments welcome :)

This patch adds support for user mode suspend to disk. It is installed in parallel to kernel mode suspend module; either will fail if system was not suspended using correct tool so next one can be tried.

---

 modules.d/95uswsusp/check             |    2 ++
 modules.d/95uswsusp/install           |    6 ++++++
 modules.d/95uswsusp/parse-uswsusp.sh  |   20 ++++++++++++++++++++
 modules.d/95uswsusp/resume-uswsusp.sh |   11 +++++++++++
 4 files changed, 39 insertions(+), 0 deletions(-)
 create mode 100755 modules.d/95uswsusp/check
 create mode 100755 modules.d/95uswsusp/install
 create mode 100755 modules.d/95uswsusp/parse-uswsusp.sh
 create mode 100755 modules.d/95uswsusp/resume-uswsusp.sh

new file mode 100755
index 0000000..ba95479
@@ -0,0 +1,2 @@
+#!/bin/sh
+[ -x /usr/sbin/resume ]

new file mode 100755
index 0000000..f8afe3a
@@ -0,0 +1,6 @@
+#!/bin/bash
+inst /usr/sbin/resume
+[ -f /etc/suspend.conf ] && inst /etc/suspend.conf
+
+inst_hook cmdline 10 "$moddir/parse-uswsusp.sh"
+inst_hook mount 10 "$moddir/resume-uswsusp.sh"

new file mode 100755
index 0000000..7a0925f
@@ -0,0 +1,20 @@
+#!/bin/sh
+if resume=$(getarg resume=) && ! getarg noresume; then 
+    export resume
+else
+    unset resume
+fi
+
+case "$resume" in
+    LABEL=*)
+	resume="$(echo $resume | sed 's,/,\\x2f,g')"
+	resume="/dev/disk/by-label/${resume#LABEL=}" ;;
+    UUID=*)
+	resume="/dev/disk/by-uuid/${resume#UUID=}" ;;
+esac
+
+if splash=$(getarg splash=); then
+    export splash
+else
+    unset splash
+fi

new file mode 100755
index 0000000..9b18567
@@ -0,0 +1,11 @@
+#!/bin/sh
+case "$splash" in
+    quiet )
+	a_splash="-P splash=y"
+    ;;
+    * )
+	a_splash="-P splash=n"
+    ;;
+esac
+
+/usr/sbin/resume $a_splash "$resume"

pushed