pic might deref a null pointer

[root at convex.UUCP]

There appears to be a (day 1?) error in portability for pic (supplied
in the ditroff distribution).

When parsing attributes with no text, pic's yacc input says, ``No text,
use a null pointer'' instead of ``No text, use a pointer to the null string''.
OOPS.

Look in picy.y for textattr appearing OUTSIDE of the attrlist
stuff.  It calls the function to make an attribute with a 0.
Change it to make the attribute with "".

I've run this for a while and it sure fixed a big problem
with dereferencing null pointers.

					Rob