[tint][cmake] Remove 'no_warning_for_no_symbols' flag

This was fixed by adding stub .cc files

Change-Id: I28aaf455188752620f09cd9f37d7aa7b96acf0dc
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/147502
Kokoro: Kokoro <noreply+kokoro@google.com>
Auto-Submit: Ben Clayton <bclayton@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Commit-Queue: Ben Clayton <bclayton@google.com>

src/tint/CMakeLists.txt

diff --git a/src/tint/CMakeLists.txt b/src/tint/CMakeLists.txt
index 1a4b172..01f4a45 100644
--- a/src/tint/CMakeLists.txt
+++ b/src/tint/CMakeLists.txt
@@ -75,11 +75,6 @@
     -Weverything
   )
 
-  if(APPLE)
-    # Silence 'has no symbols' warnings for header-only libraries.
-    target_link_options(${TARGET} PRIVATE "-no_warning_for_no_symbols")
-  endif()
-
   if(COMPILER_IS_LIKE_GNU)
     target_compile_options(${TARGET} PRIVATE
       -pedantic-errors