(trivial) randr: fix wrong call to RRGetScreenResources() in swapped case

ProcRRGetScreenResources() vs. RRGetScreenResourcesCurrent() have different semantics - this also must be followed in byte-swapped case.

Fixes: fc708394 - Add server support for RRGetScreenResourcesCurrent Signed-off-by: Enrico Weigelt, metux IT consult info@metux.net

Backport MR: !1650