Don't check the pointer is non-NULL before calling Safefree() in

Don't check the pointer is non-NULL before calling Safefree() in
little used code, code used only once per run (such as interpreter
construction and destruction), and cases where the pointer nearly
never is NULL. Safefree does its own non-NULL check, and even that
isn't strictly necessary as all conformant free()s accept a NULL
pointer.

p4raw-id: //depot/perl@25045