Add '-flto' flag to pkg-config if the libraries built with lto (#3274)

If we build Jerry libraries with lto, this information should be
passed to pkg-config as well.

JerryScript-DCO-1.0-Signed-off-by: Adam Kallai kadam@inf.u-szeged.hu

jerry-core/CMakeLists.txt

@@ -400,6 +400,11 @@ target_include_directories(${JERRY_CORE_NAME} PRIVATE ${INCLUDE_CORE_PRIVATE})
 
 set(JERRY_CORE_PKGCONFIG_REQUIRES)
 set(JERRY_CORE_PKGCONFIG_LIBS)
+set(JERRY_CORE_PKGCONFIG_CFLAGS)
+
+if(ENABLE_LTO)
+  set(JERRY_CORE_PKGCONFIG_CFLAGS "${JERRY_CORE_PKGCONFIG_CFLAGS} -flto")
+endif()
 
 if(JERRY_LIBM)
   target_link_libraries(${JERRY_CORE_NAME} jerry-libm)