hw/mem/cxl_type3: Add CXL RAS Error Injection Support.

CXL uses PCI AER Internal errors to signal to the host that an error has
occurred. The host can then read more detailed status from the CXL RAS
capability.

For uncorrectable errors: support multiple injection in one operation
as this is needed to reliably test multiple header logging support in an
OS. The equivalent feature doesn't exist for correctable errors, so only
one error need be injected at a time.

Note:
 - Header content needs to be manually specified in a fashion that
   matches the specification for what can be in the header for each
   error type.

Injection via QMP:
{ "execute": "qmp_capabilities" }
...
{ "execute": "cxl-inject-uncorrectable-errors",
  "arguments": {
    "path": "/machine/peripheral/cxl-pmem0",
    "errors": [
        {
            "type": "cache-address-parity",
            "header": [ 3, 4]
        },
        {
            "type": "cache-data-parity",
            "header": [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31]
        },
        {
            "type": "internal",
            "header": [ 1, 2, 4]
        }
        ]
  }}
...
{ "execute": "cxl-inject-correctable-error",
    "arguments": {
        "path": "/machine/peripheral/cxl-pmem0",
        "type": "physical"
    } }

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20230302133709.30373-9-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>