Differentiate between dpkg and rpm for libssl-dev

The libssl-dev package was registered in bindep.txt for both
dpkg and rpm platforms. This patch makes it use:
* libssl-dev [platform:dpkg]
* openssl-devel [platform:rpm]

Change-Id: I4a0982bf2052e193ba48c98f1b38ae569fa41be8
Closes-Bug: 1676497

bindep.txt

@@ -2,7 +2,6 @@
 # This is used by bindep: sudo [apt-get | yum] install $(bindep -b)
 
 gettext
-libssl-dev
 postgresql
 
 libffi-dev [platform:dpkg]
@@ -10,6 +9,7 @@ libffi-devel [platform:rpm]
 libldap2-dev [platform:dpkg]
 libsasl2-dev [platform:dpkg]
 libsqlite3-dev [platform:dpkg]
+libssl-dev [platform:dpkg]
 libxml2-dev [platform:dpkg]
 libxslt1-dev [platform:dpkg]
 mysql-client [platform:dpkg]
@@ -25,6 +25,7 @@ mariadb [platform:rpm]
 mariadb-devel [platform:rpm]
 mariadb-server [platform:rpm]
 openldap-devel [platform:rpm]
+openssl-devel [platform:rpm]
 postgresql-devel [platform:rpm]
 postgresql-server [platform:rpm]
 python-devel [platform:rpm]

releasenotes/notes/bug-1676497-92271e25f642e2de.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    [`bug 1676497 <https://bugs.launchpad.net/keystone/+bug/1676497>`_]
+    `bindep` now correctly reports the `openssl-devel` binary dependency for
+    rpm distros instead of `libssl-dev`.