ipmi: kcs: Finish configuring ASPEED KCS device before enable

The interrupts were configured after the channel was enabled. Configure
them beforehand so they will work.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Haiyue Wang <haiyue.wang@linux.intel.com>
Message-Id: <c0aba2c9dfe2d0525e9cefd37995983ead0ec242.1576462051.git-series.andrew@aj.id.au>
Signed-off-by: Corey Minyard <cminyard@mvista.com>