jsonrpc: Edit host restores default protocol

After editing host default value of the protocol for the host is
restored.

Bug-Url: https://bugzilla.redhat.com/1121967
Change-Id: I64f483f10b85af4891fa40c63584dbb5befc6a8e
Signed-off-by: pkliczewski <piotr.kliczewski@gmail.com>