Use -o (output to file) instead of -t (print to stdout) and a redirect.

MFC after:	1 week

share/mk/bsd.dep.mk

@@ -82,7 +82,7 @@ ${_S:R}.o: ${_S}
 .for _LSRC in ${SRCS:M*.l:N*/*}
 .for _LC in ${_LSRC:R}.c
 ${_LC}: ${_LSRC}
-	${LEX} -t ${LFLAGS} ${.ALLSRC} > ${.TARGET}
+	${LEX} ${LFLAGS} -o ${.TARGET} ${.ALLSRC}
 .if !exists(${.OBJDIR}/${DEPENDFILE})
 ${_LC:R}.o: ${_LC}
 .endif