protect against ceph not being configured yet

This is a check that /var/run/chef exists. The diff is non-scary if done whitespace independent, in which case it looks like

```
diff --git a/cookbooks/bcpc/providers/cephconfig.rb b/cookbooks/bcpc/providers/cephconfig.rb
index 66b383a..d36bf3a 100644
--- a/cookbooks/bcpc/providers/cephconfig.rb
+++ b/cookbooks/bcpc/providers/cephconfig.rb
@@ -22,6 +22,7 @@ def whyrun_supported?
 end
 
 action :set do
+  if Dir.exists?(@new_resource.path)
   Dir.chdir(@new_resource.path)
   f = Dir.glob((@new_resource.target) +".asok")
   f.each do |asok|
@@ -46,6 +47,9 @@ action :set do
       raise "Ceph target \"#{@new_resource.path}/#{asok}\" doesn't have the config value #{new_resource.name}"
     end
   end
+  else
+    Chef::Log.info("Ceph directory \"#{@new_resource.path}\" doesn't exist!")
+  end
 end
 
```