nanobts: Add support to run nanobts on the 900 band

Change-Id: I13b494630ea835f4bed38ccc77f6a4d5e18326af
diff --git a/example/resources.conf.rnd b/example/resources.conf.rnd
index 8ccf749..c263bf3 100644
--- a/example/resources.conf.rnd
+++ b/example/resources.conf.rnd
@@ -27,7 +27,7 @@
   launch_trx: true
   ciphers: [a5_0, a5_1]
 
-- label: NanoBTS
+- label: NanoBTS-ONW-1900
   type: nanobts
   ipa_unit_id: 9
   addr: 10.42.42.53