Bump host-sp-comms stacksize

[mkeeter]

The compiler bump in #1703 left us with a mere 24 bytes of stackmargin on host-sp-comms (down from about 1 KiB). This manifests as sporadic stack overflows, basically if we hit an interrupt at exactly the wrong time.

Cores are collected in /staff/dogfood/cores-collected-20240507. All of the per-task cores show the same issue:

matt@cadbury /staff/dogfood/cores-collected-20240507 () $ for f in $(find . -name "hubris.core.host_sp_comms*"); do printf "\n$f\n"; h --dump $f tasks; done

./BRM42220009/hubris.core.host_sp_comms.0
humility: attached to dump
system time = 87005911
ID TASK                       GEN PRI STATE
16 host_sp_comms                0   7 FAULT: stack overflow; sp=0x2401fff0 (was: ready)

./BRM42220017/hubris.core.host_sp_comms.0
humility: attached to dump
system time = 86463960
ID TASK                       GEN PRI STATE
16 host_sp_comms                0   7 FAULT: stack overflow; sp=0x2401ffd8 (was: ready)

./BRM44220011/hubris.core.host_sp_comms.0
humility: attached to dump
system time = 35477746
ID TASK                       GEN PRI STATE
16 host_sp_comms                0   7 FAULT: stack overflow; sp=0x2401fff0 (was: ready)

./BRM23230018-rev-d/hubris.core.host_sp_comms.1
humility: attached to dump
system time = 86618702
ID TASK                       GEN PRI STATE
16 host_sp_comms                1   7 FAULT: stack overflow; sp=0x2401fff0 (was: ready)

./BRM23230018-rev-d/hubris.core.host_sp_comms.0
humility: attached to dump
system time = 41216464
ID TASK                       GEN PRI STATE
16 host_sp_comms                0   7 FAULT: stack overflow; sp=0x2401fff0 (was: ready)

./BRM44220010/hubris.core.host_sp_comms.1
humility: attached to dump
system time = 1550511
ID TASK                       GEN PRI STATE
16 host_sp_comms                1   7 FAULT: stack overflow; sp=0x2401ffe0 (was: ready)

./BRM44220010/hubris.core.host_sp_comms.0
humility: attached to dump
system time = 1550401
ID TASK                       GEN PRI STATE
16 host_sp_comms                0   7 FAULT: stack overflow; sp=0x2401ffd0 (was: ready)

./BRM42220057/hubris.core.host_sp_comms.0
humility: attached to dump
system time = 1584024
ID TASK                       GEN PRI STATE
16 host_sp_comms                0   7 FAULT: stack overflow; sp=0x2401fff0 (was: ready)

This PR bumps us back to a healthy 1 KiB of stack margin. Figuring out why rustc decided to sabotage our stacks is left as an exercise for the reader.