linux-user: Fix error conversion in 64-bit fadvise syscall

Fix a missing host-to-target errno conversion in the 64-bit
fadvise syscall emulation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 5cff9f7..8f8d9db 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -10035,8 +10035,8 @@
         default: break;
         }
 #endif
-        ret = -posix_fadvise(arg1, arg2, arg3, arg4);
-	break;
+        ret = -host_to_target_errno(posix_fadvise(arg1, arg2, arg3, arg4));
+        break;
 #endif
 #endif /* end of 64-bit ABI fadvise handling */