vscsi: avoid unwarranted strncpy

Don't use strncpy when the source string is known to fit
in the destination buffer.  Use equivalent memcpy.
We could even use strcpy, here, but some static analyzers
warn about that, so don't add new uses.
Acked-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NJim Meyering <meyering@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

hw/spapr_vscsi.c

@@ -737,7 +737,7 @@ static int vscsi_send_adapter_info(VSCSIState *s, vscsi_req *req)
 #endif
     memset(&info, 0, sizeof(info));
     strcpy(info.srp_version, SRP_VERSION);
-    strncpy(info.partition_name, "qemu", sizeof("qemu"));
+    memcpy(info.partition_name, "qemu", sizeof("qemu"));
     info.partition_number = cpu_to_be32(0);
     info.mad_version = cpu_to_be32(1);
     info.os_type = cpu_to_be32(2);