cleanups - lots of removed files now in thread library.

qlock.c - stubs to thread library
notify.c - clean interface slightly.

src/lib9/mkfile

@@ -108,7 +108,6 @@ LIB9OFILES=\
 	jmp.$O\
 	lrand.$O\
 	lnrand.$O\
-	lock-$SYSNAME.$O\
 	main.$O\
 	malloc.$O\
 	malloctag.$O\
@@ -129,7 +128,6 @@ LIB9OFILES=\
 	quote.$O\
 	read9pmsg.$O\
 	readn.$O\
-	rendez-$SYSNAME.$O\
 	rfork.$O\
 	seek.$O\
 	sendfd.$O\
@@ -138,7 +136,6 @@ LIB9OFILES=\
 	strecpy.$O\
 	sysfatal.$O\
 	sysname.$O\
-	tas-$OBJTYPE.$O\
 	time.$O\
 	tokenize.$O\
 	truerand.$O\
@@ -164,5 +161,3 @@ HFILES=\
 
 %.$O: utf/%.c
 	$CC $CFLAGS utf/$stem.c
-
-rendez-Linux.$O: rendez-signal.c