linux-user: Fix structure target_semid64_ds definition for Mips

This patch corrects target_semid64_ds structure definition for Mips.

See, for example definition of semid64_ds for Mips in Linux kernel:
arch/mips/include/uapi/asm/sembuf.h#L13.

This patch will also fix certain semaphore-related LTP tests for Mips,
if they are executed in Qemu user mode for any Mips platform.
Signed-off-by: NMiodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: NAleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NLaurent Vivier <laurent@vivier.eu>
Reviewed-by: NLeon Alrae <leon.alrae@imgtec.com>
Acked-by: NRiku Voipio <riku.voipio@linaro.org>
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>

linux-user/mips/target_structs.h

@@ -45,4 +45,20 @@ struct target_shmid_ds {
     abi_ulong __unused2;
 };
 
+#define TARGET_SEMID64_DS
+
+/*
+ * The semid64_ds structure for the MIPS architecture.
+ * Note extra padding because this structure is passed back and forth
+ * between kernel and user space.
+ */
+struct target_semid64_ds {
+    struct target_ipc_perm sem_perm;
+    abi_ulong sem_otime;
+    abi_ulong sem_ctime;
+    abi_ulong sem_nsems;
+    abi_ulong __unused1;
+    abi_ulong __unused2;
+};
+
 #endif