Auto merge of #3270 - devnexen:android_getentropy, r=JohnTitor

getentropy addition to android

Author: bors

src/unix/linux_like/android/mod.rs

@@ -3534,7 +3534,9 @@ extern "C" {
 
     pub fn gettid() -> ::pid_t;
 
+    /// Only available in API Version 28+
     pub fn getrandom(buf: *mut ::c_void, buflen: ::size_t, flags: ::c_uint) -> ::ssize_t;
+    pub fn getentropy(buf: *mut ::c_void, buflen: ::size_t) -> ::c_int;
 
     pub fn pthread_setname_np(thread: ::pthread_t, name: *const ::c_char) -> ::c_int;