yin parser: BUGFIX: NULL dereference
yin parser: BUGFIX: NULL dereference

handle config false list with no key - we were accessing the key information
without checking that such an information is actually present. Such a
situation is valid when the list is defined as config false.

PavolVican/libyang,PavolVican/libyang,lukasmacko/libyang,PavolVican/libyang,PavolVican/libyang,lukasmacko/libyang,PavolVican/libyang