bootstrapped by `make world'.  The version just built in ".."
normally won't work if the target system is not binary compatible.
The bootstrapped version has a better chance of working.

This makes the fixes and bugs in the previous 3 commits irrelevant.
Rev.1.11 was just wrong and rev.1.10 became unnecessary when
perl/perl was added to build-tools.  Don't expect to build perl/usub
without using `make world' or equivalent if you don't have perl
installed.

Clean up an .ifdef which was probably doing the wrong thing in the case
where user wants to override PERL.
Submitted by:	jhay

CURDIR it has been built without an obj directory; however if it is in
neither of those places, we expect it to be in DESTDIR.

Yes Bruce, I know this is broken because the host is not supposed to be
the same as the target, but we need to get the hosted build working
properly first before even attempting a cross compiled operating
system build. That will need to concept of TOOLSDIR or something that
can be mapped to DESTDIR in the case of a hosted build and set to the
installed tools in a cross compiled build. Later, later, later!

perl executable from overriding the object directory path search where
perl is most likely to be. Most people haven't seen this because it
defaulted to /usr/bin/perl which might be OK as a fallback, but when
bootstrapping a new version (or the *first* version on alpha), we don't
really want to use /usr/bin/perl.

was unused afterall.

really want them) from /usr/src.  This is the final version of the
patches, incorporating the feedback I've received from -current.