Description of problem:
DiskDruid will happily allow you to specify more than 7 partitions on a DAC960
scsi/raid disk array, but /dev only contains entries for /rd/c0d0p1-/rd/c0d0p7
so when installer tries to mount c0d0p8 install barfs.

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


How reproducible:
Always

Steps to Reproduce:
1. Attempt install Redhat 8.0 with a DAC960 scsi/raid (mylex controller)
2. manually specify diskdruid partitions however you see fit, but make sure you
specify at least 8 partitions
3. continue install, and note failure mounting 8th partition right before
package installation begins
	

Actual Results:  failure mounting 8th partition right before package
installation begins

Expected Results:  install should continue normally

Additional info:

Workaround was to specify only 7 partitions per disk array.  Don't want to say
how long it took to figure that out ;-)