Fix stand-alone build for CI

Tested:
Passed the docker build.

Change-Id: If35676832ae68ed805aeeb757022a5e050f7f833
Signed-off-by: Jason M. Bills <jason.m.bills@intel.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4397728..83d2dcd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,10 +1,30 @@
 cmake_minimum_required (VERSION 3.6)
 project (peci-pcie CXX)
+include (ExternalProject)
 set (CMAKE_CXX_STANDARD 17)
 set (CMAKE_CXX_STANDARD_REQUIRED ON)
 
 add_executable (peci-pcie src/peci_pcie.cpp)
 
+option (YOCTO "Enable Building in Yocto" OFF)
+
+if (NOT YOCTO)
+    add_dependencies (peci-pcie libpeci)
+    externalproject_add (libpeci PREFIX ${CMAKE_BINARY_DIR}/libpeci
+                         GIT_REPOSITORY https://github.com/openbmc/libpeci.git
+                         GIT_TAG bc641112abc99b4a972665aa984023a6713a21ac
+                         INSTALL_COMMAND "")
+
+    externalproject_get_property (libpeci SOURCE_DIR)
+    include_directories (${SOURCE_DIR})
+
+    externalproject_get_property (libpeci BINARY_DIR)
+    add_library (peci SHARED IMPORTED)
+    set_target_properties (peci
+                           PROPERTIES IMPORTED_LOCATION
+                                      ${BINARY_DIR}/libpeci.so)
+endif ()
+
 target_include_directories (peci-pcie PRIVATE ${CMAKE_SOURCE_DIR})
 
 target_link_libraries (peci-pcie peci sdbusplus -lsystemd)