Do not segfault

how I test it outside of installation:
`ln -s / /tmp/test_root`
`/usr/lib/YaST2/bin/y2base ./test.rb UI`

content of test.rb
```
include Yast

r = WFM.SCROpen("chroot=/tmp/test_root:scr", false)
WFM.SCRSetDefault(r)
SCR.Read(path(".sysconfig.apache2"))
```