graphics/libpuzzle: Fixup r496850 and fix build of sysutils/ftwin on CURRENT

It is not puzzle-diff that needs to be linked with libm, but
libpuzzle.

ld: error: /usr/local//lib/libpuzzle.so: undefined reference to round

http://beefy12.nyi.freebsd.org/data/head-amd64-default/p500844_s347134/logs/errors/ftwin-0.8.8_4.log

graphics/libpuzzle/Makefile

@@ -2,7 +2,7 @@
 
 PORTNAME=	libpuzzle
 PORTVERSION=	0.11
-PORTREVISION=	8
+PORTREVISION=	9
 CATEGORIES=	graphics
 MASTER_SITES=	ftp://ftp.pureftpd.org/pub/pure-ftpd/misc/libpuzzle/releases/
 

graphics/libpuzzle/files/patch-src_Makefile.am

@@ -1,11 +1,11 @@
 --- src/Makefile.am.orig	2009-03-24 14:01:25 UTC
 +++ src/Makefile.am
-@@ -32,7 +32,7 @@ puzzle_diff_SOURCES = \
- 	puzzle.h
+@@ -3,6 +3,8 @@ lib_LTLIBRARIES = \
  
- puzzle_diff_LDADD = \
--	libpuzzle.la
-+	libpuzzle.la -lm
+ libpuzzle_la_LDFLAGS = -version-info 1:0
  
- TESTS = \
- 	regress_1 \
++libpuzzle_la_LIBADD = -lm
++
+ libpuzzle_la_SOURCES = \
+ 	puzzle.c \
+ 	tunables.c \