Revert "[SYCL][HIP] Mark reduction_span_pack.cpp unsupported on hip/amd (#1079)" (#1369)

This reverts commit d970da8.

@zjin-lcf has reported that this test seems to be working again on
RX-series GPUs in intel/llvm#6409

Author: dwoodwor-intel

SYCL/Reduction/reduction_span_pack.cpp

@@ -6,11 +6,6 @@
 // `Group algorithms are not supported on host device.` on Nvidia.
 // XFAIL: hip_nvidia
 
-// Disable this test on HIP/AMD until this issue has been fixed:
-// https://github.com/intel/llvm/issues/6409
-//
-// UNSUPPORTED: hip
-
 // This test performs basic checks of reductions initialized with a pack
 // containing at least one sycl::span