Progress report removal of temp files and temp relation files using ereport_startup_progress

Hi,

At times, there can be many temp files (under pgsql_tmp) and temp
relation files (under removal which after crash may take longer during
which users have no clue about what's going on in the server before it
comes up online.

Here's a proposal to use ereport_startup_progress to report the
progress of the file removal.

Thoughts?

Regards,
Bharath Rupireddy.