api,bearer: new 'profile-id' setting

We define a new 'profile-id' setting in the bearer properties that
users will use to specify which connection profile of the ones
available in the device should be connected.

When the 'profile-id' is given, the associated bearer object will be
bound to the 'profile-id', and the user is able to provide additional
settings to apply on top (e.g. if the profile storage doesn't allow
some of the settings we support, like 'apn-type', or if the setting is
completely unrelated to profiles, like 'multiplex').

After introducing the 'profile-id' as a valid setting in the bearer
properties, we also reimplement the properties object internals to
make use a 3GPP profile for the subset of common settings between both
objects.

cli/mmcli-output.h

@@ -235,6 +235,7 @@ typedef enum {
     MMC_F_BEARER_PROPERTIES_ALLOWED_AUTH,
     MMC_F_BEARER_PROPERTIES_USER,
     MMC_F_BEARER_PROPERTIES_PASSWORD,
+    MMC_F_BEARER_PROPERTIES_PROFILE_ID,
     MMC_F_BEARER_PROPERTIES_NUMBER,
     MMC_F_BEARER_PROPERTIES_RM_PROTOCOL,
     MMC_F_BEARER_IPV4_CONFIG_METHOD,