p-exp.y: parse error before "xmalloc"

[Michael Chastain]

It's the problem that Andreas Schwab noticed.

p-exp.y says:

  char *uptokstart = (char *)malloc(namelen+1);

p-exp.c, after substitution, says:

  char *uptokstart = (char *xmalloc(namelen+1);

I'll go ahead and check in a patch unless someone beats me to it.

Michael