meta-aspeed: linux: Enable CONFIG_IPMI_KCS_BMC_CDEV_IPMI

The CONFIG_IPMI_KCS_BMC_CDEV_IPMI is necessary for the new KCS driver
refactor to create the ipmi-kcs devices.

Tested: Verify on g220a that the ipmi-kcs3/4 devices are created and the
        inband IPMI via KCS works fine.

Signed-off-by: Lei YU <yulei.sh@bytedance.com>
Change-Id: I2a1e7842f231fb4ee8284c194ed9cf28f668885e
diff --git a/meta-aspeed/recipes-kernel/linux/linux-aspeed/aspeed-g6/defconfig b/meta-aspeed/recipes-kernel/linux/linux-aspeed/aspeed-g6/defconfig
index 48e2e75..b648a27 100644
--- a/meta-aspeed/recipes-kernel/linux/linux-aspeed/aspeed-g6/defconfig
+++ b/meta-aspeed/recipes-kernel/linux/linux-aspeed/aspeed-g6/defconfig
@@ -153,6 +153,7 @@
 CONFIG_SERIAL_8250_DW=y
 CONFIG_SERIAL_OF_PLATFORM=y
 CONFIG_ASPEED_KCS_IPMI_BMC=y
+CONFIG_IPMI_KCS_BMC_CDEV_IPMI=y
 CONFIG_IPMI_KCS_BMC_SERIO=y
 CONFIG_ASPEED_BT_IPMI_BMC=y
 CONFIG_HW_RANDOM_TIMERIOMEM=y