This patch fixes processing of rfi instructions in icount mode.

In this mode writing to interrupt/peripheral state is controlled
by can_do_io flag. This flag must be set explicitly before helper
function invocation.

Signed-off-by: Maria Klimushenkova <maria.klimushenkova@ispras.ru>
Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>