rpm: compile modules for plus with openssl11 in Amazon Linux 2

Match changes made to Nginx Plus builds in R24

rpm/SPECS/nginx-plus-module.spec.in

diff --git a/rpm/SPECS/nginx-plus-module.spec.in b/rpm/SPECS/nginx-plus-module.spec.in
index b142dc4..ee62e86 100644
--- a/rpm/SPECS/nginx-plus-module.spec.in
+++ b/rpm/SPECS/nginx-plus-module.spec.in
@@ -10,8 +10,12 @@
 
 %if 0%{?rhel} || 0%{?amzn}
 %define _group System Environment/Daemons
+%if 0%{?amzn} >= 2
+BuildRequires: openssl11-devel
+%else
 BuildRequires: openssl-devel
 %endif
+%endif
 
 %if 0%{?suse_version} >= 1315
 %define _group Productivity/Networking/Web/Servers