Bitfield enums don't cast correctly in Blueprints

The licensee already investigated this a little. The problem appears to be that UKismetNodeHelperLibrary::GetValidValue should be calling IsValidEnumValueOrBitfield as opposed to IsValidEnumValue.

1. Create a blueprint actor with 2 properties a byte and an enum with bitflags set, such as EMappingQueryIssue.
2. Set the byte property to value "3". This is a valid EMappingQueryIssue Bitflag combination that represents both ReservedByAction and HidesExistingMapping.
3. Drag the byte property onto the graph to create a "get" node.
4. Drag the enum property onto the graph to create a "set" node.
5. Connect the nodes. An extra conversion node will be created.
6. Drag the byte property onto the graph to create a "set" node.
7. Connect the Set Enum node output to the Set Byte value node.
8. Create a Print String node and connect the byte set value node output to it.
9. Create an instance of the actor in the level.
10. Run PIE
11. Current behavior: 33 is printed to the screen.
12. Expected behavior: 3 is printed to the screen.