build: enable meson build

Add meson build support.  Autotools support will be removed in
the future once the consuming meta-phosphor recipes are updated.

This should be feature complete relative to the previous autotools
support.

Additionally, support is added for using sdbusplus as a subproject
in the event that users do not have sdbusplus installed.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ic2c0129bda11cf10aaa557c2fd6403e2ed2cd8dd
diff --git a/subprojects/sdbusplus.wrap b/subprojects/sdbusplus.wrap
new file mode 100644
index 0000000..d470130
--- /dev/null
+++ b/subprojects/sdbusplus.wrap
@@ -0,0 +1,3 @@
+[wrap-git]
+url = https://github.com/openbmc/sdbusplus.git
+revision = HEAD