Error Handling
For configuratrion and I/O (non-posted) writes, the PCIe Controller might
receive a completion with error status from the PCIe link. In this case, the PCIe Controller issues an error response (i.e., SLVERR) on the AXI
slave write response channel's MASTER_AXI_BRESP output by asserting
MASTER_AXI_BVALID.