api,dbus: rename AllowedBands' to just Bands'

ModemManager will load:
  1) The list of supported bands. Note that this doesn't mean that any possible
     combination of bands is supported, as modems may support only specific
     combinations, but at least gives a rough idea of what the modem is capable
     of handling.

  2) The list of CURRENT bands. There is no such "Allowed" bands, as we do with
     modes, modems will have a specific set of bands being currently used, which
     will be reported in the `Bands' property.

If the modem allows modifying the list of bands to use, this can be done with
the `SetBands()' method. If the modem doesn't support using a specific
combination of bands, this method will report an error.

new/org.freedesktop.ModemManager1.Modem.xml

@@ -136,13 +136,13 @@
     </method>
 
     <!--
-        SetAllowedBands:
-        @bands: List of <link linkend="MMModemBand">MMModemBand</link> values, to specify all the bands allowed in the modem.
+        SetBands:
+        @bands: List of <link linkend="MMModemBand">MMModemBand</link> values, to specify the bands to be used.
 
         Set the radio frequency and technology bands the device is currently
         allowed to use when connecting to a network.
     -->
-    <method name="SetAllowedBands">
+    <method name="SetBands">
       <arg name="bands" type="au" direction="in" />
     </method>
 
@@ -419,19 +419,15 @@
     <property name="SupportedBands" type="au" access="read" />
 
     <!--
-        AllowedBands:
+        Bands:
 
         List of <link linkend="MMModemBand">MMModemBand</link> values,
         specifying the radio frequency and technology bands the device is
-        currently allowed to use when connecting to a network.
+        currently using when connecting to a network.
 
         It must be a subset of #org.freedesktop.ModemManager1.Modem:SupportedBands.
-
-        For POTS devices, only the
-        <link linkend="MM-MODEM-BAND-ANY:CAPS"><constant>MM_MODEM_BAND_ANY</constant></link>
-        mode is supported.
     -->
-    <property name="AllowedBands" type="au" access="read" />
+    <property name="Bands" type="au" access="read" />
 
   </interface>
 </node>