R: add missing dependency on libxml2

srcpkgs/R/template

@@ -11,7 +11,7 @@ hostmakedepends="gcc-fortran pkg-config perl less"
 makedepends="libgomp-devel readline-devel libXmu-devel libXt-devel
  libpng-devel libjpeg-turbo-devel tiff-devel cairo-devel icu-devel
  lapack-devel blas-devel zlib-devel bzip2-devel pcre-devel liblzma-devel
- libcurl-devel tcl-devel tk-devel"
+ libcurl-devel tcl-devel tk-devel libxml2-devel"
 depends="xdg-utils less"
 short_desc="System for statistical computation and graphics"
 maintainer="Florian Wagner <florian@wagner-flo.net>"