documentation for the macro "allow_role_transitions"

initializes role transition data including the implicit self-transition.

It is defined in the file sets.m4.

m4 code:

define(`allow_role_transitions',
`define(role_transitionsX$1,patsubst(patsubst(notmember(`
$1
',patsubst(`$2',`
',`)notmember(`
$1
',')),`
$',)
$1,^
,))')