[proaudio] compile errors against libxml2

[audio-mobster <audio-mobster@xxxxxx>]

audio-mobster schrieb:
> If you get errors compiling against libxml2, the pkg-config file was
> renamed. Just do:
> 
> cp /usr/lib/pkgconfig/libxml-2.0.pc  /usr/lib/pkgconfig/xml2.pc
> 
If this mail is usefull these keywords will be too:
PKG_CONFIG_PATH xml2 libxml libxml2 xml2.pc error problem
configure: error: Package requirements (libxml2) were not met:
No package 'libxml2' found