Use namespaces to link against libcereal >= 1.3.1

Create an alias for previous versions.

CMakeLists.txt

@@ -506,6 +506,9 @@ endif ()
 
 # Find the Cereal serialization library
 find_package(cereal REQUIRED)
+if (NOT TARGET cereal::cereal)
+    add_library(cereal::cereal ALIAS cereal)
+endif ()
 
 # l10n
 set(L10N_DIR "${SLIC3R_RESOURCES_DIR}/localization")

src/CMakeLists.txt

@@ -126,7 +126,7 @@ if (NOT WIN32 AND NOT APPLE)
     set_target_properties(PrusaSlicer PROPERTIES OUTPUT_NAME "prusa-slicer")
 endif ()
 
-target_link_libraries(PrusaSlicer libslic3r cereal)
+target_link_libraries(PrusaSlicer libslic3r cereal::cereal)
 if (APPLE)
 #    add_compile_options(-stdlib=libc++)
 #    add_definitions(-DBOOST_THREAD_DONT_USE_CHRONO -DBOOST_NO_CXX11_RVALUE_REFERENCES -DBOOST_THREAD_USES_MOVE)

src/libslic3r/CMakeLists.txt

@@ -358,7 +358,7 @@ find_package(JPEG REQUIRED)
 target_link_libraries(libslic3r
     libnest2d
     admesh
-    cereal
+    cereal::cereal
     libigl
     miniz
     boost_libs

src/slic3r/CMakeLists.txt

@@ -270,7 +270,7 @@ endforeach()
 
 encoding_check(libslic3r_gui)
 
-target_link_libraries(libslic3r_gui libslic3r avrdude cereal imgui GLEW::GLEW OpenGL::GL hidapi libcurl ${wxWidgets_LIBRARIES})
+target_link_libraries(libslic3r_gui libslic3r avrdude cereal::cereal imgui GLEW::GLEW OpenGL::GL hidapi libcurl ${wxWidgets_LIBRARIES})
 
 if (MSVC)
     target_link_libraries(libslic3r_gui Setupapi.lib)