musl: Reorganize some statfs-related types for a cleaner diff

This moves similar types together (e.g. statfs and statfs64) so removing
them is cleaner.

Co-authored-by: Andy Caldwell <andycaldwell@microsoft.com>

(backport <rust-lang#3261>)
(cherry picked from commit 6c0952e)

Author: tgross35

src/unix/linux_like/linux/musl/b32/x86/mod.rs

@@ -46,6 +46,10 @@ s! {
         pub st_ino: ::ino_t,
     }
 
+    pub struct mcontext_t {
+        __private: [u32; 22],
+    }
+
     pub struct stack_t {
         pub ss_sp: *mut ::c_void,
         pub ss_flags: ::c_int,
@@ -112,10 +116,6 @@ s! {
         pub f_spare: [::c_ulong; 4],
     }
 
-    pub struct mcontext_t {
-        __private: [u32; 22],
-    }
-
     pub struct siginfo_t {
         pub si_signo: ::c_int,
         pub si_errno: ::c_int,

src/unix/linux_like/linux/musl/b64/mod.rs

@@ -3,36 +3,6 @@ pub type c_ulong = u64;
 pub type regoff_t = ::c_long;
 
 s! {
-    pub struct statfs64 {
-        pub f_type: ::c_ulong,
-        pub f_bsize: ::c_ulong,
-        pub f_blocks: ::fsblkcnt_t,
-        pub f_bfree: ::fsblkcnt_t,
-        pub f_bavail: ::fsblkcnt_t,
-        pub f_files: ::fsfilcnt_t,
-        pub f_ffree: ::fsfilcnt_t,
-        pub f_fsid: ::fsid_t,
-        pub f_namelen: ::c_ulong,
-        pub f_frsize: ::c_ulong,
-        pub f_flags: ::c_ulong,
-        pub f_spare: [::c_ulong; 4],
-    }
-
-    pub struct statvfs64 {
-        pub f_bsize: ::c_ulong,
-        pub f_frsize: ::c_ulong,
-        pub f_blocks: u64,
-        pub f_bfree: u64,
-        pub f_bavail: u64,
-        pub f_files: u64,
-        pub f_ffree: u64,
-        pub f_favail: u64,
-        pub f_fsid: ::c_ulong,
-        pub f_flag: ::c_ulong,
-        pub f_namemax: ::c_ulong,
-        __f_spare: [::c_int; 6],
-    }
-
     pub struct stack_t {
         pub ss_sp: *mut ::c_void,
         pub ss_flags: ::c_int,
@@ -89,6 +59,36 @@ s! {
         pub f_spare: [::c_ulong; 4],
     }
 
+    pub struct statfs64 {
+        pub f_type: ::c_ulong,
+        pub f_bsize: ::c_ulong,
+        pub f_blocks: ::fsblkcnt_t,
+        pub f_bfree: ::fsblkcnt_t,
+        pub f_bavail: ::fsblkcnt_t,
+        pub f_files: ::fsfilcnt_t,
+        pub f_ffree: ::fsfilcnt_t,
+        pub f_fsid: ::fsid_t,
+        pub f_namelen: ::c_ulong,
+        pub f_frsize: ::c_ulong,
+        pub f_flags: ::c_ulong,
+        pub f_spare: [::c_ulong; 4],
+    }
+
+    pub struct statvfs64 {
+        pub f_bsize: ::c_ulong,
+        pub f_frsize: ::c_ulong,
+        pub f_blocks: u64,
+        pub f_bfree: u64,
+        pub f_bavail: u64,
+        pub f_files: u64,
+        pub f_ffree: u64,
+        pub f_favail: u64,
+        pub f_fsid: ::c_ulong,
+        pub f_flag: ::c_ulong,
+        pub f_namemax: ::c_ulong,
+        __f_spare: [::c_int; 6],
+    }
+
     pub struct msghdr {
         pub msg_name: *mut ::c_void,
         pub msg_namelen: ::socklen_t,