enchant-lsmod.c: show provider error if any when request_dict fails
enchant-lsmod.c: show provider error if any when request_dict fails

This should prevent confusion such as that which led to
https://github.com/AbiWord/enchant/issues/289

AbiWord/enchant,rrthomas/enchant,AbiWord/enchant,rrthomas/enchant,rrthomas/enchant,AbiWord/enchant,AbiWord/enchant,rrthomas/enchant