linux-user: Use unique error messages for cmsg parsing

Avoid using the same error message for two different code paths
as it complicates determining the one which actually triggered.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>

Author: hdeller

linux-user/syscall.c

@@ -1827,7 +1827,7 @@ static inline abi_long target_to_host_cmsg(struct msghdr *msgh,
                 *dst = tswap32(*dst);
             }
         } else {
-            qemu_log_mask(LOG_UNIMP, "Unsupported ancillary data: %d/%d\n",
+            qemu_log_mask(LOG_UNIMP, "Unsupported target ancillary data: %d/%d\n",
                           cmsg->cmsg_level, cmsg->cmsg_type);
             memcpy(data, target_data, len);
         }
@@ -2049,7 +2049,7 @@ static inline abi_long host_to_target_cmsg(struct target_msghdr *target_msgh,
 
         default:
         unimplemented:
-            qemu_log_mask(LOG_UNIMP, "Unsupported ancillary data: %d/%d\n",
+            qemu_log_mask(LOG_UNIMP, "Unsupported host ancillary data: %d/%d\n",
                           cmsg->cmsg_level, cmsg->cmsg_type);
             memcpy(target_data, data, MIN(len, tgt_len));
             if (tgt_len > len) {