rsync: backport libattr checking patch

rsync: backport libattr checking patch

Add check_libattr.patch to version 3.1.0 recipe, which checks
and includes libattr to linker, otherwise rsync may fail to build
with linker error below (as -lattr option gets omitted):

[..]
lib/sysxattrs.o: undefined reference to symbol 'llistxattr@@ATTR_1.0'
[..]/lib/libattr.so.1: error adding symbols: DSO missing from command line

Signed-off-by: Sergiy Kibrik <sakib@meta.ua>
Signed-off-by: Armin Kuster <akuster@mvista.com>