Remove checking that vectors were copied to RAM as not all targets
have NVIC_RAM_VECTOR_ADDRESS defined as public. Instead always
call NVIC_SetVector unconditionally as old implementation does.
When a Doxygen group has been defined (created), all its needed to add
documentation to that group is `\addtogroup`. Since all the information
about the group is preserved, it is not necessary to mention the group
hierarchy again with `\ingroup`. This PR removes unnecessary Doxygen lines
across the `drivers`, `events`, `platform` and `rtos` directories.
It also ensures that new groups are created with `\defgroup` once and
referenced with `\addtogroup` whenever documentation needs to be added to
an existing group.
Martin Kojtal
Maciej Bocianski
Hugues Kamba
George Psimenos