pkgsrc bootstrap AIX 4.1

["Larson, Timothy E." <TELarson%west.com@localhost>]

I recently hacked around enough to get bootstrapped on AIX 4.1.5 and was going 
to submit the patches.  In one place where I had to link libc_r to get support 
for thread-safe functions, I made it conditional on OPSYS=AIX just to see if I 
could get it working on my box.  But I was thinking it would probably be better 
to check for the libc_r library, and be conditional on that - assuming that if 
the system supplies one, it must be necessary for reentrant calls.  I know that 
on AIX >= 4.3 libc_r is just a link to libc, so it should be OK either way, but 
by checking the library we might gain something for other systems too, not just 
AIX.

Comments?

Thanks,
Tim