profile library memory leaks introduced when malloc returns 0

profile library memory leaks introduced when malloc returns 0

I have a modified version of valgrind that will allow me to have
malloc fail in a controlled way.  A number of memory leaks in error return
passes exist in the profile library.  They are essentially inconsequental - but
my goal is to eventually create a test harness that tries to cover all code -
including error returns...

prof_parse.c: (profile_parse_file): Free node being created if
	      parse_line() fails.

prof_file.c (profile_open_file): free prf_data_t on malloc failure

prof_tree.c (profile_create_node): The magic element must be set
	    before calling profile_free_node for it to release memory.

ticket: new

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@19981 dc483132-0cff-0310-8789-dd5450dbe970