Pike 7.2 don't recognice postgres after upgrade to postgres 7.2.1

Imported from http://bugzilla.roxen.com/bugzilla/show_bug.cgi?id=3338

Reported by Robert Nilsson, robert@rnn.nu

I'm running Red Hat Linux 7.3 with Postgres v7.2.1, Roxen 3.3 and pike 7.2 (release 433). After I upgraded Postgres from v7.0 to 7.2.1 pike (and therefore also Roxen) didn't support postgres anymore. "pike --features" didn't list "postgres".

I upgraded Roxen from v2.2 to v3.3, but still no support of Postgres...

Finally found that pike was using Postgres c library "/usr/lib/libpq.so.2.1", but that has been replaced by "libpq.so.2.2".

Solution: Made a symbolic link of the old name to the new: ln -s libpq.so.2.2 libpq.so.2.1 and then Postgres was supported in Pike again.