build system: move -fno-rtti link option next to the compile option

Previous commit has added `link_options` to the root CMakeLists.txt,
can use it to collect such global link options now.

CMakeLists.txt

@@ -32,6 +32,7 @@ if(CONFIG_COMPILER_CXX_RTTI)
     list(APPEND cxx_compile_options "-frtti")
 else()
     list(APPEND cxx_compile_options "-fno-rtti")
+    list(APPEND link_options "-fno-rtti")           # used to invoke correct multilib variant (no-rtti) during linking
 endif()
 
 if(CONFIG_COMPILER_DISABLE_GCC8_WARNINGS)

components/cxx/CMakeLists.txt

@@ -15,7 +15,3 @@ target_link_libraries(${COMPONENT_LIB} PUBLIC stdcpp_pthread)
 if(NOT CONFIG_COMPILER_CXX_EXCEPTIONS)
     target_link_libraries(${COMPONENT_LIB} INTERFACE "-u __cxx_fatal_exception")
 endif()
-
-if(NOT CONFIG_COMPILER_CXX_RTTI)
-    target_link_libraries(${COMPONENT_LIB} PUBLIC -fno-rtti)
-endif()