Simplify some_default_match logic

Prior to this commit, the Puppet::Provider.some_default_match method
used a case statement to determine whether to match facts or feature.

Because that case statement only had one condition, this commit
simplifies the logic to instead use a ternary if.

Author: mhashizume

lib/puppet/provider.rb

@@ -273,12 +273,7 @@ def self.default_match
   def self.some_default_match(defaultlist)
     defaultlist.find do |default|
       default.all? do |key, values|
-        case key
-          when :feature
-            feature_match(values)
-          else
-            fact_match(key, values)
-        end
+        key == :feature ? feature_match(values) : fact_match(key, values)
       end
     end
   end