Bug 1499038

Description of problem:
executed liveinst on a f26 spin, this exception comes up together with language selection screen within a few seconds.

Version-Release number of selected component:
anaconda-core-26.21.12-1.fc26.x86_64

The following was filed automatically by anaconda:
anaconda 26.21.12-1 exception report
Traceback (most recent call first):
  File "/usr/lib64/python3.6/site-packages/pyanaconda/payload/livepayload.py", line 195, in _updateKernelVersionList
    files.extend(glob.glob(INSTALL_TREE + "/boot/efi/EFI/%s/vmlinuz-*" % self.instclass.efi_dir))
  File "/usr/lib64/python3.6/site-packages/pyanaconda/payload/livepayload.py", line 87, in setup
    self._updateKernelVersionList()
  File "/usr/lib64/python3.6/site-packages/pyanaconda/payload/__init__.py", line 1432, in _runThread
    payload.setup(storage, instClass)
  File "/usr/lib64/python3.6/threading.py", line 864, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib64/python3.6/site-packages/pyanaconda/threads.py", line 251, in run
    threading.Thread.run(self)
AttributeError: 'DefaultInstall' object has no attribute 'efi_dir'

Additional info:
addons:         com_redhat_kdump
cmdline:        /usr/libexec/system-python  /sbin/anaconda --liveinst --method=livecd:///dev/mapper/live-base
cmdline_file:   BOOT_IMAGE=vmlinuz0 initrd=initrd0.img root=live:CDLABEL=fx64_x86_64 rootfstype=auto ro rd.live.image quiet  rhgb rd.luks=0 rd.md=0 rd.dm=0 
executable:     /sbin/anaconda
hashmarkername: anaconda
kernel:         4.12.14-300.fc26.x86_64
other involved packages: system-python-libs-3.6.2-7.fc26.x86_64
product:        Fedora
release:        FX64 release 26 (Twenty Six)
type:           anaconda
version:        26