build-unit-test-docker: add libunifex

unifex is a library that sdbusplus will begin to depend on in order to
support co-routines.  Add it here to match the recipe that has been
submitted upstream.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I4548813cba19822c1367c3de1b81cc2f034518c6
diff --git a/scripts/build-unit-test-docker b/scripts/build-unit-test-docker
index dd0eeb5..e79e9d4 100755
--- a/scripts/build-unit-test-docker
+++ b/scripts/build-unit-test-docker
@@ -191,6 +191,17 @@
         build_type="custom",
         build_steps=[f"cp src/fifo_map.hpp {prefix}/include/"],
     ),
+    # version from meta-openembedded/meta-oe/recipes-devtools/unifex/unifex_git.bb
+    "facebookexperimental/libunifex": PackageDef(
+        rev="9df21c58d34ce8a1cd3b15c3a7347495e29417a0",
+        build_type="cmake",
+        config_flags=[
+            "-DBUILD_SHARED_LIBS=ON",
+            "-DBUILD_TESTING=OFF",
+            "-DCMAKE_CXX_STANDARD=20",
+            "-DUNIFEX_BUILD_EXAMPLES=OFF",
+        ],
+    ),
     "open-power/pdbg": PackageDef(build_type="autoconf"),
     "openbmc/gpioplus": PackageDef(
         depends=["openbmc/stdplus"],
@@ -251,6 +262,9 @@
         ],
     ),
     "openbmc/sdbusplus": PackageDef(
+        depends=[
+            "facebookexperimental/libunifex",
+        ],
         build_type="meson",
         custom_post_dl=[
             "cd tools",