Fix inhibiting the default.el loading in user init file

Fix inhibiting the default.el loading in user init file

* lisp/startup.el (startup--load-user-init-file): Test the value
of 'inhibit-default-init', not just the LOAD-DEFAULTS argument,
because loading the user's init file could have set the value of
the former.
(command-line): Call 'startup--load-user-init-file' with last arg
t: there's no longer any need to test the value of
'inhibit-default-init' here, as it will be tested by the called
function.  (Bug#45708)