After the commit b8b541f, the system would not start up properly
with certain coldboot conditions. For example, if the OpenSBI picked
hart4 as the coldboot hart in preference to hart3, the system would
get stuck due to stack corruption. OpenSBI uses a lottery mechanism
to pick the coldboot hart.
Also fix g_scratches area in such a manner than it will not get
initialized to zero. If several harts initialize the area to zero, there's
danger the stack pointer gets wiped out.
Now any coldboot hart works.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
b7d2b38700