ControlCard slot id

[LimeHat]

bootz.proto defines control card slot id as a numeric (int32) value

bootz/proto/bootz.proto

Lines 75 to 80 in b8d7fb3

	// Details of the control card, including serial-number and the location
	// of the card on the chassis.
	message ControlCard {
	string part_number = 1;
	string serial_number = 2;
	int32 slot = 3;

, however OpenConfig uses type string for component ID and location leafs:
https://github.com/openconfig/public/blob/cd1cfcd263d033ee5f9b10cddde6f823f6cb30e2/release/models/platform/openconfig-platform.yang#L391, and not all vendors use numeric values for control cards.

Can this be changed to string?

cc @xw-g

[gmacf]

This sounds sensible. Changing proto field types is risky but I can make a new field called "slot_id" or similar and eventually deprecate the old one.