Add initial osmo-remsim usermanual

Change-Id: I1d9231b24b1481afcbb5758662b7d99bd59e7fdb
diff --git a/doc/manuals/chapters/remsim-bankd.adoc b/doc/manuals/chapters/remsim-bankd.adoc
index a3e708d..11a8811 100644
--- a/doc/manuals/chapters/remsim-bankd.adoc
+++ b/doc/manuals/chapters/remsim-bankd.adoc
@@ -12,8 +12,8 @@
 
 *-h, --help*::
   Print a short help message about the supported options
-*-i, --server-ip A.B.C.D*::
-  Specify the remote IP address of the remsim-server to which this bankd
+*-i, --server-host A.B.C.D*::
+  Specify the remote IP address/hostname of the remsim-server to which this bankd
   shall establish its <<RSPRO>> control connection
 *-p, --server-port <1-65535>*::
   Specify the remote TCP port number of the remsim-server to whihc this bankd