File gun-1.1.0-otp_release.patch of Package gun

diff -Ndurp gun-1.1.0/src/gun.erl gun-1.1.0-otp_release/src/gun.erl
--- gun-1.1.0/src/gun.erl	2018-08-06 18:02:46.000000000 +0300
+++ gun-1.1.0-otp_release/src/gun.erl	2019-09-28 01:45:43.796764475 +0300
@@ -15,8 +15,10 @@
 -module(gun).
 
 -ifdef(OTP_RELEASE).
+-if (?OTP_RELEASE >= 21).
 -compile({nowarn_deprecated_function, [{erlang, get_stacktrace, 0}]}).
 -endif.
+-endif.
 
 %% Connection.
 -export([open/2]).