Broken on recent amazon linux

[dividedmind]

Amazon Linux has diverged from RHEL so much that it's its own platform family in chef now. Simply forcing the checks to rhel fail on installing the ssh server.

[infamousjoeg]

@dividedmind https://docs.chef.io/deprecations_ohai_amazon_linux.html

[infamousjoeg]

Replace:
if platform_family?('rhel')
with
if platform_family?('rhel', 'amazon')

We will be POCing this with the customer next week.