Description of problem:
Installing over a system with multiple disk devices present, one with content that needs to be maintained results in Anaconda's configuration showing that two conflicting options were used for the device which was ignored with a volumegroup present:

#volgroup STOR --noformat --useexisting --pesize=4096
 
--noformat, which specifies to use an existing logical volume and *** do not format *** it. 
--useexisting, which specifies to use an existing logical volume and *** reformat *** it.

This is clearly not optimal as it creates what can only be described as a race condition between the two options. The result is the current state which has data available on the disk/VG in question (confirmed using dd and hexdump) but no clear way to tell the system how to access it post-install.

Version-Release number of selected component (if applicable):
5.7

How reproducible:
Do nothing with an existing/detected VG in the installer and the above flags will be applied, resulting in the LVM data being lost do to the apparent formatting of the disk/LUN.


Steps to Reproduce:
1. Run the installer, ignoring a specific device (eg /dev/sdb)
2. Wait for the install to finish, verify that pvs / pvdisplay no longer shows the PV 
3. No profit.
  
Actual results:
See above.

Expected results:
Device configuration is left alone/as-is with no changes or modifications to the device.

Additional info:
The installer detects the configuration of the PV and VG without issue, so clearly the problem takes place as part of the installation. SF # affiliated with bug = 00635279