Log Message:
Fix tcl/tk configure script stupidity: it overwrote the value of LDFLAGS
that accumulates within itself with a do-nothing version because it tried
to re-use LDFLAGS for another purpose.  This broke all library checks after
the "checking for ELF" step.  Fix this by (duh) not re-using LDFLAGS but
by using a different variable.  Bump the PKGREVISIONs of lang/tcl and
x11/tk.

This fixes building the threaded versions of tcl and tk.