#4754 some limits of the form ind/ind

[Barton Willis]

Maxima gets some limits of the form ind/ind correct; for example

(%i12) limit(sin(x)/(3+sin(x)),x,inf);
(%o12)                                ind

But Maxima misses other cases:

(%i13) limit(sin(x)/(3+sin(x)+cos(x)),x,inf);
(%o13)                                und