Fix controller_hostname in install.sh for AIO

Ibdb436ce0f removed a bad ip->hostname mapping from
data/data_mappings/common.yaml and replaced it with an
explicit declaration of coe::base::controller_hostname
in user.common.yaml.  However: in an AIO install the
install.sh script doesn't do anything to override the
sample value from user.common.yaml, so it always gets
set to 'control-server' regardless of the node's actual
hostname.  This patch explicitly sets the value in the
install.sh script to avoid this problem.

Change-Id: I2f4f7d8e3b50cf22015e9445b697458f854f16e0
Partial-Bug: #1274263
Merge "Fix controller_hostname in install.sh for AIO"