Fix link with HTML5 lib and LTO

Author: ifiddynine

tools/system_libs.py

@@ -2038,7 +2038,7 @@ class libhtml5(Library):
   cflags = ['-Oz', '-fno-inline-functions']
   src_dir = 'system/lib/html5'
   src_glob = '*.c'
-
+  force_object_files = True
 
 class CompilerRTLibrary(Library):
   cflags = ['-fno-builtin']