meson: Add subprojects file

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: Ie2cf5f445e7939ce394a43ae2a59901e1550ff53
diff --git a/subprojects/phosphor-host-ipmid.wrap b/subprojects/phosphor-host-ipmid.wrap
new file mode 100644
index 0000000..29bb550
--- /dev/null
+++ b/subprojects/phosphor-host-ipmid.wrap
@@ -0,0 +1,8 @@
+[wrap-git]
+url = https://github.com/openbmc/phosphor-host-ipmid.git
+revision = HEAD
+
+[provide]
+libipmid = ipmid_dep
+libchannellayer = channellayer_dep
+libuserlayer = userlayer_dep