t9501: Re-fix max load test

Revert the previous attempt to skip this test on platforms where we currently cannot determine the system load. We want to make sure that the max-load-limit codepath produces results cleanly, when gitweb is updated and becomes capable of reading the load average by some other method. The code to check for load returns 0 if it doesn't know how to find load. It also checks to see if the current load is higher than the max load. So to force the script to quit early by setting the maxload variable negative which should work for systems where we can detect load (which should be a positive number) and systems where we can't (where detected load is 0) Signed-off-by: Brian Gernhardt <brian@gernhardtsoftware.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>