* init/environ.c (environ_all_valid): Only verify that an = is present
(environ_valid): Drop this function, the part of POSIX I read about
valid environment variable names only applies to other things defined
by POSIX, elsewhere it explicitly says Applications may do whatever
they like (and even encourages to avoid conflict)
(environ_expand_until): Remove validity check for name.
* init/environ.h: Update header.
* init/tests/test_environ.c (test_valid): Drop tests.
(test_all_valid): Drop name tests.
(test_expand): Remove illegal expansion test.
* init/tests/test_control.c (test_emit_event): Remove the test case for
an invalid name in the environment.
* init/tests/test_job_class.c (test_start, test_stop)
(test_restart): Change the invalid argument tests to use an entry
without an = as the invalid test.