Fix const for field tm_zone in struct tm

src/unix/bsd/apple/mod.rs

@@ -262,6 +262,20 @@ s! {
         __unused8: Padding<*mut c_void>,
     }
 
+    pub struct tm {
+        pub tm_sec: c_int,
+        pub tm_min: c_int,
+        pub tm_hour: c_int,
+        pub tm_mday: c_int,
+        pub tm_mon: c_int,
+        pub tm_year: c_int,
+        pub tm_wday: c_int,
+        pub tm_yday: c_int,
+        pub tm_isdst: c_int,
+        pub tm_gmtoff: c_long,
+        pub tm_zone: *mut c_char,
+    }
+
     pub struct addrinfo {
         pub ai_flags: c_int,
         pub ai_family: c_int,

src/unix/bsd/freebsdlike/mod.rs

@@ -121,6 +121,20 @@ s! {
         __unused8: Padding<*mut c_void>,
     }
 
+    pub struct tm {
+        pub tm_sec: c_int,
+        pub tm_min: c_int,
+        pub tm_hour: c_int,
+        pub tm_mday: c_int,
+        pub tm_mon: c_int,
+        pub tm_year: c_int,
+        pub tm_wday: c_int,
+        pub tm_yday: c_int,
+        pub tm_isdst: c_int,
+        pub tm_gmtoff: c_long,
+        pub tm_zone: *mut c_char,
+    }
+
     pub struct addrinfo {
         pub ai_flags: c_int,
         pub ai_family: c_int,

src/unix/bsd/mod.rs

@@ -74,20 +74,6 @@ s! {
         fds_bits: [i32; FD_SETSIZE as usize / 32],
     }
 
-    pub struct tm {
-        pub tm_sec: c_int,
-        pub tm_min: c_int,
-        pub tm_hour: c_int,
-        pub tm_mday: c_int,
-        pub tm_mon: c_int,
-        pub tm_year: c_int,
-        pub tm_wday: c_int,
-        pub tm_yday: c_int,
-        pub tm_isdst: c_int,
-        pub tm_gmtoff: c_long,
-        pub tm_zone: *mut c_char,
-    }
-
     pub struct msghdr {
         pub msg_name: *mut c_void,
         pub msg_namelen: crate::socklen_t,

src/unix/bsd/netbsdlike/netbsd/mod.rs

@@ -161,6 +161,20 @@ s! {
         __unused8: Padding<*mut c_void>,
     }
 
+    pub struct tm {
+        pub tm_sec: c_int,
+        pub tm_min: c_int,
+        pub tm_hour: c_int,
+        pub tm_mday: c_int,
+        pub tm_mon: c_int,
+        pub tm_year: c_int,
+        pub tm_wday: c_int,
+        pub tm_yday: c_int,
+        pub tm_isdst: c_int,
+        pub tm_gmtoff: c_long,
+        pub tm_zone: *mut c_char,
+    }
+
     pub struct mq_attr {
         pub mq_flags: c_long,
         pub mq_maxmsg: c_long,

src/unix/bsd/netbsdlike/openbsd/mod.rs

@@ -84,6 +84,20 @@ s! {
         __unused7: Padding<*mut c_void>,
     }
 
+    pub struct tm {
+        pub tm_sec: c_int,
+        pub tm_min: c_int,
+        pub tm_hour: c_int,
+        pub tm_mday: c_int,
+        pub tm_mon: c_int,
+        pub tm_year: c_int,
+        pub tm_wday: c_int,
+        pub tm_yday: c_int,
+        pub tm_isdst: c_int,
+        pub tm_gmtoff: c_long,
+        pub tm_zone: *const c_char,
+    }
+
     pub struct lconv {
         pub decimal_point: *mut c_char,
         pub thousands_sep: *mut c_char,