iommu/intel: Fix memleak in intel_irq_remapping_alloc

iommu/intel: Fix memleak in intel_irq_remapping_alloc

When irq_domain_get_irq_data() or irqd_cfg() fails
at i == 0, data allocated by kzalloc() has not been
freed before returning, which leads to memleak.

Fixes: 7d103896b28c ("irq_remapping/vt-d: Enhance Intel IR driver to support hierarchical irqdomains")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210105051837.32118-1-dinghao.liu@zju.edu.cn
Signed-off-by: Will Deacon <will@kernel.org>