Add mihawk platform to meta-ibm

The contents of this up-stream include the following items
1.Basic function
2.Led settings
3.GPIO monitor (id button and power supply)
4.Linux dts patch.

(From meta-ibm rev: c53430a2234917b71f29d7e61d6aea749c45a2fc)

Change-Id: Id0e47fd9197c8b2a70cbc94888bd572255664cdd
Signed-off-by: Ben Pai <Ben_Pai@wistron.com>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-ibm/meta-witherspoon/recipes-phosphor/mboxd/mboxd_%.bbappend b/meta-ibm/meta-witherspoon/recipes-phosphor/mboxd/mboxd_%.bbappend
index 69c9d1d..589405e 100644
--- a/meta-ibm/meta-witherspoon/recipes-phosphor/mboxd/mboxd_%.bbappend
+++ b/meta-ibm/meta-witherspoon/recipes-phosphor/mboxd/mboxd_%.bbappend
@@ -1,4 +1,5 @@
 MBOXD_FLASH_SIZE_ibm-ac-server = "64M"
+MBOXD_FLASH_SIZE_mihawk = "64M"
 
 FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:"