api,introspection: update 'Validity' property in the SMS interface

We don't want to support only 'relative' validity, so don't assume that the
Validity property will always be a uint32 value.

Instead, we define the Validity propery as '(uv)' tuple, where the first value
(a MMSmsValidityType) specifies the type of validity, and the second value is
a variant formatted accordingly to what the validity type specifies (e.g. a
uint32 value if the type is MM_SMS_VALIDITY_TYPE_RELATIVE).

docs/reference/libmm-glib/libmm-glib-sections.txt

@@ -885,7 +885,8 @@ mm_sms_get_smsc
 mm_sms_dup_smsc
 mm_sms_get_message_reference
 mm_sms_get_class
-mm_sms_get_validity
+mm_sms_get_validity_type
+mm_sms_get_validity_relative
 mm_sms_get_timestamp
 mm_sms_dup_timestamp
 mm_sms_get_discharge_timestamp
@@ -979,6 +980,7 @@ mm_sms_pdu_type_get_string
 mm_sms_state_get_string
 mm_sms_delivery_state_get_string
 mm_sms_storage_get_string
+mm_sms_validity_type_get_string
 mm_firmware_image_type_get_string
 <SUBSECTION Private>
 mm_modem_capability_get_string
@@ -994,6 +996,7 @@ mm_sms_pdu_type_build_string_from_mask
 mm_sms_state_build_string_from_mask
 mm_sms_delivery_state_build_string_from_mask
 mm_sms_storage_build_string_from_mask
+mm_sms_validity_type_build_string_from_mask
 mm_modem_location_source_get_string
 mm_modem_contacts_storage_build_string_from_mask
 mm_bearer_ip_family_build_string_from_mask
@@ -1034,6 +1037,7 @@ MM_TYPE_SMS_DELIVERY_STATE
 MM_TYPE_SMS_PDU_TYPE
 MM_TYPE_SMS_STATE
 MM_TYPE_SMS_STORAGE
+MM_TYPE_SMS_VALIDITY_TYPE
 mm_bearer_ip_family_get_type
 mm_bearer_ip_method_get_type
 mm_bearer_allowed_auth_get_type
@@ -1060,6 +1064,7 @@ mm_sms_delivery_state_get_type
 mm_sms_pdu_type_get_type
 mm_sms_state_get_type
 mm_sms_storage_get_type
+mm_sms_validity_type_get_type
 </SECTION>
 
 <SECTION>
@@ -2317,6 +2322,7 @@ mm_gdbus_sms_dup_number
 mm_gdbus_sms_get_smsc
 mm_gdbus_sms_dup_smsc
 mm_gdbus_sms_get_validity
+mm_gdbus_sms_dup_validity
 mm_gdbus_sms_get_class
 mm_gdbus_sms_get_timestamp
 mm_gdbus_sms_dup_timestamp