runtests: add 'wakeup' as a feature

tests/FILEFORMAT.md

@@ -405,6 +405,7 @@ Features testable here are:
 - `unittest`
 - `unix-sockets`
 - `verbose-strings`
+- `wakeup`
 - `win32`
 
 as well as each protocol that curl supports.  A protocol only needs to be

tests/runtests.pl

@@ -2823,6 +2823,7 @@ sub setupfeatures {
     $feature{"shuffle-dns"} = 1;
     $feature{"typecheck"} = 1;
     $feature{"verbose-strings"} = 1;
+    $feature{"wakeup"} = 1;
 
 }