hardware:bugfix: AirGrid M2 0x212 remove power offset to facilitate testing

Removing the offset and increasing max power so we have full range avaliable to us.

This may not help us figure out the offset but will allow us a wider range of options.

ref BBHN->ticket:71

files/www/cgi-bin/perlfunc.pm

@@ -1003,8 +1003,8 @@ sub hardware_info
             'name'            => 'airGrid M2',
             'comment'         => 'airGrid M2 -- Reported as an hp',
             'supported'       => '-2',
-            'maxpower'        => '18',
-            'pwroffset'       => '10',
+            'maxpower'        => '28',
+            'pwroffset'       => '0',
             'antennas'        => { 1 => 'airGrid' },
             'defaultant'      => 1,
             'usechains'       => 0,