Remove imprecise and unnecessary HOME ownership check.

When looking for the pulse home directory, we currently check to see if HOME is owned by us. This check is imprecise, because what we actually care about is being able to create a subdirectory of ~/.pulse or $XDG_CONFIG_HOME/pulse, and unnecessary, because if we don't have the appropriate permissions we will get an appropriate failure when we try to create the subdirectory immediately after this function call (and the normal TOCTOU concerns apply).

This check was added in a9c80b43, and nothing in the commit message indicates why it would be needed.