pkg/45757: audio/libaudiofile: add configure check for libm

[matthias.rampke%googlemail.com@localhost]

>Number:         45757
>Category:       pkg
>Synopsis:       audio/libaudiofile: add configure check for libm
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Dec 29 14:40:01 +0000 2011
>Originator:     Matthias Rampke
>Release:        DragonFly HEAD
>Organization:
>Environment:
DragonFly tp.2pktfkt.net 2.13-DEVELOPMENT DragonFly 
v2.13.0.623.g2c104-DEVELOPMENT #0: Wed Dec 21 06:48:14 UTC 2011     
root%pkgbox32.dragonflybsd.org@localhost:/usr/obj/usr/src/sys/GENERIC  i386
>Description:
the configure script of libaudiofile does not check for libm, therefore the -lm 
LDFLAG is not included, causing compilation e.g. on DragonFly to fail.
>How-To-Repeat:
build audio/libaudiofile on dragonfly
>Fix:
https://gist.github.com/1534351

submitted upstream: https://github.com/mpruett/audiofile/pull/6/files