gnu sparc: Use a separate stat struct for 32bit powerpc

Like mips and powerpc, the stat struct will become different once
support for gnu_file_offset_bits64 is added.

(backport <rust-lang#4345>)
(cherry picked from commit e134959)

Author: snogge

src/unix/linux_like/linux/gnu/b32/mod.rs

@@ -54,7 +54,8 @@ cfg_if! {
     if #[cfg(not(any(
         target_arch = "mips",
         target_arch = "mips32r6",
-        target_arch = "powerpc"
+        target_arch = "powerpc",
+        target_arch = "sparc"
     )))] {
         s! {
             pub struct stat {

src/unix/linux_like/linux/gnu/b32/sparc/mod.rs

@@ -60,6 +60,29 @@ s! {
         pub ss_size: size_t,
     }
 
+    pub struct stat {
+        pub st_dev: crate::dev_t,
+        __pad1: c_ushort,
+        pub st_ino: crate::ino_t,
+        pub st_mode: crate::mode_t,
+        pub st_nlink: crate::nlink_t,
+        pub st_uid: crate::uid_t,
+        pub st_gid: crate::gid_t,
+        pub st_rdev: crate::dev_t,
+        __pad2: c_ushort,
+        pub st_size: off_t,
+        pub st_blksize: crate::blksize_t,
+        pub st_blocks: crate::blkcnt_t,
+        pub st_atime: crate::time_t,
+        pub st_atime_nsec: c_long,
+        pub st_mtime: crate::time_t,
+        pub st_mtime_nsec: c_long,
+        pub st_ctime: crate::time_t,
+        pub st_ctime_nsec: c_long,
+        __glibc_reserved4: c_ulong,
+        __glibc_reserved5: c_ulong,
+    }
+
     pub struct stat64 {
         pub st_dev: crate::dev_t,
         pub st_ino: crate::ino64_t,