Exclude parenthesized function declarations such as NORETURN

Fixes ruby/ruby#3883

Author: nobu

lib/rdoc/parser/c.rb

@@ -572,7 +572,7 @@ def gen_body_table file_content
       ((?>/\*.*?\*/\s*)?)
       ((?:(?:\w+)\s+)?
         (?:intern\s+)?VALUE\s+(\w+)
-        \s*(?:\([^)]*\))(?:[^;]|$))
+        \s*(?:\([^)]*\))(?:[^\);]|$))
     | ((?>/\*.*?\*/\s*))^\s*(\#\s*define\s+(\w+)\s+(\w+))
     | ^\s*\#\s*define\s+(\w+)\s+(\w+)
     }xm) do