trap_handler_wrapper: Fix stack setup in the wrong direction
trap_handler_wrapper: Fix stack setup in the wrong direction

As the stack grows downwards, the offset for stack allocation must be
negative. Unfortunately, the stack allocation in the wrong direction
lead to the trap handler wrapper overwriting itself with the register
dump.

ChristianMoesl/selfie,cksystemsteaching/selfie,cksystemsteaching/selfie,cksystemsteaching/selfie,ChristianMoesl/selfie