alpha: _TIF_ALLWORK_MASK is unused

... and never had been used, actually
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/alpha/include/asm/thread_info.h

@@ -77,10 +77,6 @@ register struct thread_info *__current_thread_info __asm__("$8");
 #define _TIF_WORK_MASK		(_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
 				 _TIF_NOTIFY_RESUME | _TIF_NOTIFY_SIGNAL)
 
-/* Work to do on any return to userspace.  */
-#define _TIF_ALLWORK_MASK	(_TIF_WORK_MASK		\
-				 | _TIF_SYSCALL_TRACE)
-
 #define TS_UAC_NOPRINT		0x0001	/* ! Preserve the following three */
 #define TS_UAC_NOFIX		0x0002	/* ! flags as they match          */
 #define TS_UAC_SIGBUS		0x0004	/* ! userspace part of 'osf_sysinfo' */