Fixed LDADD. Using ${LIBM} instead of -lm gave the wrong libm in most

cases and broke the world in some cases.

Fixed some style bugs (the usual ones for DPADD and LDADD, misplacement
of DPADD and LDADD, and misplacement of $FreeBSD$).

bin/df/Makefile

@@ -1,5 +1,5 @@
-# $FreeBSD$
 #	@(#)Makefile	8.3 (Berkeley) 5/8/95
+# $FreeBSD$
 
 PROG=	df
 SRCS=	df.c vfslist.c
@@ -8,8 +8,9 @@ BINMODE=2555
 
 MOUNT=	${.CURDIR}/../../sbin/mount
 CFLAGS+= -I${MOUNT}
-LDADD+= ${LIBM}
-DPADD+= ${LIBM}
 .PATH:	${MOUNT}
 
+DPADD=	${LIBM}
+LDADD=	-lm
+
 .include <bsd.prog.mk>