meta-ampere: move ipmi config to common

The same channel_config.json and power_reading.json are used across
Ampere platforms so move to meta-ampere/meta-common to avoid duplicate.

Tested:
1. Check if "ipmitool lan print 1/2/3" works.
2. On Mt.Jade, check if "ipmitool dcmi power reading" works

Signed-off-by: Thang Q. Nguyen <thang@os.amperecomputing.com>
Change-Id: I77f401d0b74455c3951fb746f8bea2ddb1c3667b
diff --git a/meta-ampere/meta-common/recipes-phosphor/ipmi/phosphor-ipmi-config.bbappend b/meta-ampere/meta-common/recipes-phosphor/ipmi/phosphor-ipmi-config.bbappend
new file mode 100644
index 0000000..eadb7e4
--- /dev/null
+++ b/meta-ampere/meta-common/recipes-phosphor/ipmi/phosphor-ipmi-config.bbappend
@@ -0,0 +1 @@
+FILESEXTRAPATHS:append := "${THISDIR}/${PN}:"