Fix some minor issues with the SYSV init and initramfs scripts.

This is some minor fixes to commits 2cac7f5f11
and 2a34db1bdb.

* Make sure to alien'ate the new initramfs rpm package as well!
  The rpm package is build correctly, but alien isn't run on it to
  create the deb.
* Before copying file from COPY_FILE_LIST, make sure the DESTDIR/dir exists.
* Include /lib/udev/vdev_id file in the initrd.
* Because the initrd needs to use '/sbin/modprobe' instead of 'modprobe',
  we need to use this in load_module() as well.
  * Make sure that load_module() can be used more globaly, instead of
    calling '/sbin/modprobe' all over the place.
  * Make sure that check_module_loaded() have a parameter - module to
    check.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3626

contrib/initramfs/scripts/zfs

@@ -282,7 +282,7 @@ load_module_initrd()
 	[ ! -f /etc/mtab ] && cat /proc/mounts > /etc/mtab
 
 	# Load the module
-	load_module || return 1
+	load_module "zfs" || return 1
 
 	if [ "$ZFS_INITRD_POST_MODPROBE_SLEEP" > 0 ]
 	then
@@ -388,7 +388,7 @@ decrypt_fs()
 	do
 		[ "$quiet" != "y" ] && zfs_log_progress_msg "${mod} "
 
-		ZFS_CMD="/sbin/modprobe $mod"
+		ZFS_CMD="load_module $mod"
 		ZFS_STDERR="$(${ZFS_CMD} 2>&1)"
 		ZFS_ERROR="$?"