Why does Red Hat Enterprise Linux 7.6 SystemZ KVM Guest fail to install with error " FormatCreateError ('invalid device specification', '/dev/vda1')" ?

Issue

• Why does Red Hat Enterprise Linux 7.6 SystemZ KVM Guest fail to install with error message mentioned ahead.
• There is a Red Hat Enterprise Linux 7.6 IBM Z which is being used as a KVM hypervisor.
• While creating a disk, say /dev/disk/by-path/ccw-0.0.5240 and formatting it with dasdfmt and presenting it to the kvm machine as raw disk, the kvm is taking that as a raw disk, naming it as vda and then installation stops at the following traceback.

12:12:22,503 INFO anaconda: Creating disklabel on /dev/vda
12:12:22,559 INFO anaconda: Created disklabel on /dev/vda
12:12:22,776 INFO anaconda: Creating xfs on /dev/vda1
12:12:22,820 DEBUG anaconda: running handleException
12:12:22,820 CRIT anaconda: Traceback (most recent call last):
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 227, in run
    threading.Thread.run(self, *args, **kwargs)
  File "/usr/lib64/python2.7/threading.py", line 765, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/install.py", line 206, in doInstall
    turnOnFilesystems(storage, mountOnly=flags.flags.dirInstall, callbacks=callbacks_reg)
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 235, in turnOnFilesystems
    storage.doIt(callbacks)
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 386, in doIt
    self.devicetree.processActions(callbacks)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 377, in processActions
    action.execute(callbacks)
  File "/usr/lib/python2.7/site-packages/blivet/deviceaction.py", line 569, in execute
    options=self.device.formatArgs)
  File "/usr/lib/python2.7/site-packages/blivet/formats/fs.py", line 899, in create
    DeviceFormat.create(self, **kwargs)
  File "/usr/lib/python2.7/site-packages/blivet/formats/__init__.py", line 384, in create
    raise FormatCreateError("invalid device specification", self.device)
FormatCreateError: ('invalid device specification', '/dev/vda1')

• The partitions which are going to be created are as follows

# System bootloader configuration
bootloader --append=" crashkernel=auto" --location=mbr --boot-drive=vda
autopart --type=lvm
# Partition clearing information
clearpart --all --initlabel --drives=vda

• The disk it has taken from the raw device from background as follows.

    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='native' iothread='1'/>
      <source dev='/dev/disk/by-path/ccw-0.0.5240'/>
      <target dev='vda' bus='virtio'/>
      <address type='ccw' cssid='0xfe' ssid='0x0' devno='0x5240'/>
    </disk>