linux-user: correct how SOL_SOCKET is converted from target to host and back

Previous implementation does not take into account that SOL_SOCKET constant
can be arch specific. This change fixes some issues with sendmsg/recvmsg.

Signed-off-by: Petar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 7a093ba..aebe36d 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -1150,11 +1150,15 @@
             break;
         }
 
-        cmsg->cmsg_level = tswap32(target_cmsg->cmsg_level);
+        if (tswap32(target_cmsg->cmsg_level) == TARGET_SOL_SOCKET) {
+            cmsg->cmsg_level = SOL_SOCKET;
+        } else {
+            cmsg->cmsg_level = tswap32(target_cmsg->cmsg_level);
+        }
         cmsg->cmsg_type = tswap32(target_cmsg->cmsg_type);
         cmsg->cmsg_len = CMSG_LEN(len);
 
-        if (cmsg->cmsg_level != TARGET_SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) {
+        if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) {
             gemu_log("Unsupported ancillary data: %d/%d\n", cmsg->cmsg_level, cmsg->cmsg_type);
             memcpy(data, target_data, len);
         } else {
@@ -1205,11 +1209,15 @@
             break;
         }
 
-        target_cmsg->cmsg_level = tswap32(cmsg->cmsg_level);
+        if (cmsg->cmsg_level == SOL_SOCKET) {
+            target_cmsg->cmsg_level = tswap32(TARGET_SOL_SOCKET);
+        } else {
+            target_cmsg->cmsg_level = tswap32(cmsg->cmsg_level);
+        }
         target_cmsg->cmsg_type = tswap32(cmsg->cmsg_type);
         target_cmsg->cmsg_len = tswapal(TARGET_CMSG_LEN(len));
 
-        if ((cmsg->cmsg_level == TARGET_SOL_SOCKET) &&
+        if ((cmsg->cmsg_level == SOL_SOCKET) &&
                                 (cmsg->cmsg_type == SCM_RIGHTS)) {
             int *fd = (int *)data;
             int *target_fd = (int *)target_data;
@@ -1217,7 +1225,7 @@
 
             for (i = 0; i < numfds; i++)
                 target_fd[i] = tswap32(fd[i]);
-        } else if ((cmsg->cmsg_level == TARGET_SOL_SOCKET) &&
+        } else if ((cmsg->cmsg_level == SOL_SOCKET) &&
                                 (cmsg->cmsg_type == SO_TIMESTAMP) &&
                                 (len == sizeof(struct timeval))) {
             /* copy struct timeval to target */