acpi/acpigen: add acpigen_resource_bus_number to generate bus number

Add the acpigen_resource_bus_number helper function to generate a bus
number range resource.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Change-Id: Ib1f1da3dbe823c6bc4fc30c0622653410cfbf301
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75043
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <inforichland@gmail.com>

src/include/acpi/acpigen.h

@@ -693,6 +693,8 @@ void acpigen_resource_dword(u16 res_type, u16 gen_flags, u16 type_flags,
 void acpigen_resource_qword(u16 res_type, u16 gen_flags, u16 type_flags,
 	u64 gran, u64 range_min, u64 range_max, u64 translation, u64 length);
 
+void acpigen_resource_bus_number(u16 bus_base, u16 bus_limit);
+
 /* Emits Notify(namestr, value) */
 void acpigen_notify(const char *namestr, int value);