[FreeBSD] Cmake build should not set U_TIMEZONE for FreeBSD (#54)

* should not set U_TIMEZONE for FreeBSD

* add comment

Author: michael-yuji

CMakeLists.txt

@@ -81,6 +81,8 @@ elseif(CMAKE_SYSTEM_NAME STREQUAL "WASI")
         $<$<COMPILE_LANGUAGE:C,CXX>:_WASI_EMULATED_MMAN>)
     add_link_options("-Lwasi-emulated-signal")
     add_link_options("-Lwasi-emulated-mman")
+elseif(CMAKE_SYSTEM_NAME STREQUAL FreeBSD)
+    # On FreeBSD, we should not set U_TIMEZONE
 else()
     add_compile_definitions(
         $<$<COMPILE_LANGUAGE:C,CXX>:U_TIMEZONE=timezone>)