linux-user: Fix target_stat and target_stat64 for OpenRISC

OpenRISC uses the asm-generic versions of target_stat and
target_stat64, but it was incorrectly using the x86/ARM/etc version
due to a misplaced defined(TARGET_OPENRISC).  The previously unused
OpenRISC section of the ifdef ladder also defined an incorrect
target_stat and omitted the target_stat64 definition.  Fix
target_stat, provide target_stat64, and add a comment noting that
these are the asm-generic versions for the benefit of future ports.

Reviewed-by: Jia Liu <proljc@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>

linux-user/syscall_defs.h

@@ -1138,8 +1138,7 @@ struct target_winsize {
 #endif
 
 #if (defined(TARGET_I386) && defined(TARGET_ABI32)) || defined(TARGET_ARM) \
-    || defined(TARGET_CRIS) || defined(TARGET_UNICORE32) \
-    || defined(TARGET_OPENRISC)
+    || defined(TARGET_CRIS) || defined(TARGET_UNICORE32)
 struct target_stat {
 	unsigned short st_dev;
 	unsigned short __pad1;
@@ -1837,29 +1836,55 @@ struct target_stat {
     abi_ulong  __unused[3];
 };
 #elif defined(TARGET_OPENRISC)
+
+/* These are the asm-generic versions of the stat and stat64 structures */
+
 struct target_stat {
     abi_ulong st_dev;
     abi_ulong st_ino;
-    abi_ulong st_nlink;
-
     unsigned int st_mode;
+    unsigned int st_nlink;
     unsigned int st_uid;
     unsigned int st_gid;
-    unsigned int __pad0;
     abi_ulong st_rdev;
+    abi_ulong __pad1;
     abi_long st_size;
-    abi_long st_blksize;
-    abi_long st_blocks;    /* Number 512-byte blocks allocated. */
-
-    abi_ulong target_st_atime;
+    int st_blksize;
+    int __pad2;
+    abi_long st_blocks;
+    abi_long target_st_atime;
     abi_ulong target_st_atime_nsec;
-    abi_ulong target_st_mtime;
+    abi_long target_st_mtime;
     abi_ulong target_st_mtime_nsec;
-    abi_ulong target_st_ctime;
+    abi_long target_st_ctime;
     abi_ulong target_st_ctime_nsec;
+    unsigned int __unused4;
+    unsigned int __unused5;
+};
 
-    abi_long __unused[3];
+struct target_stat64 {
+    uint64_t st_dev;
+    uint64_t st_ino;
+    unsigned int st_mode;
+    unsigned int st_nlink;
+    unsigned int st_uid;
+    unsigned int st_gid;
+    uint64_t st_rdev;
+    uint64_t __pad1;
+    int64_t st_size;
+    int st_blksize;
+    int __pad2;
+    int64_t st_blocks;
+    int target_st_atime;
+    unsigned int target_st_atime_nsec;
+    int target_st_mtime;
+    unsigned int target_st_mtime_nsec;
+    int target_st_ctime;
+    unsigned int target_st_ctime_nsec;
+    unsigned int __unused4;
+    unsigned int __unused5;
 };
+
 #else
 #error unsupported CPU
 #endif