Remove the new extern "C" blocks (merge with existing blocks)

Author: niluxv

src/unix/bsd/freebsdlike/mod.rs

@@ -1591,9 +1591,7 @@ extern "C" {
         outbytesleft: *mut ::size_t,
     ) -> ::size_t;
     pub fn iconv_close(cd: iconv_t) -> ::c_int;
-}
 
-extern "C" {
     // Added in `FreeBSD` 11.0
     // Added in `DragonFly BSD` 5.4
     pub fn explicit_bzero(s: *mut ::c_void, len: ::size_t);

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

@@ -2083,9 +2083,7 @@ extern "C" {
         outbytesleft: *mut ::size_t,
     ) -> ::size_t;
     pub fn iconv_close(cd: iconv_t) -> ::c_int;
-}
 
-extern "C" {
     // Added in `NetBSD` 7.0
     pub fn explicit_memset(b: *mut ::c_void, c: ::c_int, len: ::size_t);
 }

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

@@ -1543,9 +1543,7 @@ extern "C" {
     pub fn freelocale(loc: ::locale_t);
     pub fn newlocale(mask: ::c_int, locale: *const ::c_char, base: ::locale_t) -> ::locale_t;
     pub fn duplocale(base: ::locale_t) -> ::locale_t;
-}
 
-extern "C" {
     // Added in `OpenBSD` 5.5
     pub fn explicit_bzero(s: *mut ::c_void, len: ::size_t);
 }

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

@@ -1233,6 +1233,9 @@ extern "C" {
         newpath: *const ::c_char,
         flags: ::c_uint,
     ) -> ::c_int;
+
+    // Added in `glibc` 2.25
+    pub fn explicit_bzero(s: *mut ::c_void, len: ::size_t);
 }
 
 extern "C" {
@@ -1300,11 +1303,6 @@ extern "C" {
     pub fn dlinfo(handle: *mut ::c_void, request: ::c_int, info: *mut ::c_void) -> ::c_int;
 }
 
-extern "C" {
-    // Added in `glibc` 2.25
-    pub fn explicit_bzero(s: *mut ::c_void, len: ::size_t);
-}
-
 cfg_if! {
     if #[cfg(any(target_arch = "x86",
                  target_arch = "arm",

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

@@ -697,9 +697,7 @@ extern "C" {
         path: *const ::c_char,
     ) -> ::c_int;
     pub fn getauxval(type_: ::c_ulong) -> ::c_ulong;
-}
 
-extern "C" {
     // Added in `musl` 1.1.20
     pub fn explicit_bzero(s: *mut ::c_void, len: ::size_t);
 }