Fixed issue where AC_CHECK_LIB was polluting LIBS with -lxml.
Fixed issue where AC_CHECK_LIB was polluting LIBS with -lxml.

Original commit message from CVS:
Fixed issue where AC_CHECK_LIB was polluting LIBS with -lxml.

magcius/gstreamer,mparis/gstreamer,surround-io/gstreamer,centricular/gstreamer,collects/gstreamer,krieger-od/gstreamer,shelsonjava/gstreamer,cfoch/gstreamer,lovebug356/gstreamer,mrchapp/gstreamer,surround-io/gstreamer,drothlis/gstreamer,ahmedammar/platform_external_gst_gstreamer,krieger-od/gstreamer,Lachann/gstreamer,lubosz/gstreamer,cablelabs/gstreamer,jpakkane/gstreamer,surround-io/gstreamer,jpxiong/gstreamer,centricular/gstreamer,justinjoy/gstreamer,krichter722/gstreamer,lubosz/gstreamer,Lachann/gstreamer,mparis/gstreamer,jpakkane/gstreamer,krichter722/gstreamer,ylatuya/gstreamer,lovebug356/gstreamer,cablelabs/gstreamer,StreamUtils/gstreamer,StreamUtils/gstreamer,collects/gstreamer,Distrotech/gstreamer,mrchapp/gstreamer,shelsonjava/gstreamer,jpakkane/gstreamer,cablelabs/gstreamer,ensonic/gstreamer,krichter722/gstreamer,Distrotech/gstreamer,collects/gstreamer,cfoch/gstreamer,lovebug356/gstreamer,centricular/gstreamer,jpxiong/gstreamer,krieger-od/gstreamer,jpxiong/gstreamer,justinjoy/gstreamer,Distrotech/gstreamer,magcius/gstreamer,mrchapp/gstreamer,cfoch/gstreamer,ahmedammar/platform_external_gst_gstreamer,shelsonjava/gstreamer,cfoch/gstreamer,justinjoy/gstreamer,StreamUtils/gstreamer,StreamUtils/gstreamer,drothlis/gstreamer,StreamUtils/gstreamer,krichter722/gstreamer,lubosz/gstreamer,surround-io/gstreamer,Lachann/gstreamer,krieger-od/gstreamer,krieger-od/gstreamer,lovebug356/gstreamer,justinjoy/gstreamer,collects/gstreamer,ylatuya/gstreamer,jpakkane/gstreamer,mparis/gstreamer,ahmedammar/platform_external_gst_gstreamer,collects/gstreamer,cablelabs/gstreamer,jpxiong/gstreamer,ensonic/gstreamer,drothlis/gstreamer,surround-io/gstreamer,jpxiong/gstreamer,magcius/gstreamer,jpakkane/gstreamer,lubosz/gstreamer,ylatuya/gstreamer,ensonic/gstreamer,lubosz/gstreamer,ahmedammar/platform_external_gst_gstreamer,shelsonjava/gstreamer,cfoch/gstreamer,mparis/gstreamer,mrchapp/gstreamer,krichter722/gstreamer,centricular/gstreamer,mparis/gstreamer,centricular/gstreamer,justinjoy/gstreamer,Lachann/gstreamer,Distrotech/gstreamer,ensonic/gstreamer,ylatuya/gstreamer,Lachann/gstreamer,ylatuya/gstreamer,ahmedammar/platform_external_gst_gstreamer,lovebug356/gstreamer,magcius/gstreamer,Distrotech/gstreamer,ensonic/gstreamer,drothlis/gstreamer,drothlis/gstreamer,mrchapp/gstreamer,shelsonjava/gstreamer,magcius/gstreamer,cablelabs/gstreamer