arch/arm/raspberry_pi: mailbox: Check for errors more strictly

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
arch/arm: Map interrupt vectors properly

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
arch/arm: Handle aborts more gracefully

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>
arch/arm: Relax register constraints in disable/enable interrupts

Signed-off-by: Pawel Dziepak <pdziepak@quarnos.org>