swig: wrap lyd_validate_value() as member of the Schema object
swig: wrap lyd_validate_value() as member of the Schema object

lyd_validate_value() is applicable on schema nodes even without
having a data tree.

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