Bug#56875: Hang when using net_fetch for OS

[Jim Studt <jim@federated.com>]

Package: boot-floppies
Version: 2.2.4

When booted on an NFS root and installing onto a local hard drive
dbootstrap hangs in nf_extract_kernel.  It does the get_device()
which does 
	if (is_nfs_partition("/instmnt"))
... is_nfs_partition calls mounted_reread (for the 2nd time in the 
program) which produces a cirularly linked mounted_partitions list.
(very bad when it gets traversed.)

The problem is probably related to fdisk_find_partition_by_name() 
returning the already existing entry and then linking it in to the
mounted_partitions list near the end of the mounted_reread() function.

I'm still working on the ARM support so I can test this for the next
couple days if you come up with a fix.

-- 
                                     Jim Studt, President
                                     The Federated Software Group, Inc.