Wrong unpacked structure for epoll_event on qemu-or1k (openrisc)

Host environment

• Operating system: Slackware GNU/Linux
• OS/kernel version: Linux ryzen 6.1.14 #1 SMP PREEMPT_DYNAMIC Sat Feb 25 13:52:36 CST 2023 x86_64 AMD Ryzen 7 3700X 8-Core Processor AuthenticAMD GNU/Linux
• Architecture: x86_64
• QEMU flavor: qemu-or1k (user)
• QEMU version: 8.0.50 (git commit hash 4633c1e2)

Emulated/Virtualized environment

• Operating system: GNU/Linux OpenRISC user-space
• Architecture: or1k (OpenRISC)

Description of problem

When using cmake automoc, the process will infinite loop waiting for epoll_events.

Steps to reproduce

1. Try to compile cmake with qt5 support
2. The build process will freeze when "Automatic MOC" is invoked

Additional information

The problem is that or1k has a "packed" epoll_event structure, so it should be also packed in target_epoll_event structure. Following the (very trivial) patch:

--- qemu-20230327/linux-user/syscall_defs.h.orig	2023-03-27 15:41:42.000000000 +0200
+++ qemu-20230327/linux-user/syscall_defs.h	2023-06-30 17:29:39.034322213 +0200
@@ -2714,7 +2709,7 @@ 
 #define FUTEX_CMD_MASK          ~(FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME)
 
 #ifdef CONFIG_EPOLL
-#if defined(TARGET_X86_64)
+#if defined(TARGET_X86_64) || defined(TARGET_OPENRISC)
 #define TARGET_EPOLL_PACKED QEMU_PACKED
 #else
 #define TARGET_EPOLL_PACKED