Fix conditional dependency on missing target

Author: DannyDaemonic

examples/main/CMakeLists.txt

@@ -2,4 +2,6 @@ set(TARGET main)
 add_executable(${TARGET} main.cpp)
 target_link_libraries(${TARGET} PRIVATE common llama ${CMAKE_THREAD_LIBS_INIT})
 target_compile_features(${TARGET} PRIVATE cxx_std_11)
-add_dependencies(${TARGET} BUILD_INFO)
+if(TARGET BUILD_INFO)
+  add_dependencies(${TARGET} BUILD_INFO)
+endif()