i_alloc: shave another 60 bytes off
kn_open: shave off 30 bytes
process: Add loadav calculator.

Needs to be exposed nicely to userspace yet.

Also remove a dead FIXME in the process code
z80pack: remove facepalm
Makefile: put string constants from the startup into discard as well

This lets us undo the buffer hack in a bit
binman: Pack the _DISCARD section so it can be relocated and discarded

This means platforms need to adjust their crt0.s as per the following
z80pack commits
z80pack: Keep discard separate

We can now discard the _DISCARD segment - yay, another 1K
z80pack: link _DISCARD at 0xE000
kdata,start: undo the bufpool hack

The strings should now end up in _DISCARD without hackery