Kernel support for Z180 CPUs
cpm-loader: Tools to make a CP/M application which boots the Fuzix kernel
cpm-loader: Fix minor typo in comment
Kernel: Improve simple timer code. Remove timer.h include where it is not required.
Kernel: Allow boot device number to be greater than 9
Kernel: lowlevel-z80: Remove unused map_process symbol
Kernel: Whitespace fix for start.c
Kernel: Increment both 16-bit and 32-bit tick counters on every timer interrupt
Kernel: Add N8VEM Mark 4 and DX-Designs P112 platforms
Kernel: Tidy up p112 and n8vem-mark4 targets, remove redundant code and merge memory mapping functions into common Z180 code.
Kernel: Bug fix -- on system call, touch kernel_flag only after switching to the kernel memory bank
Kernel: Remove obsolete lines from kernel.def on p112 and n8vem-mark4 platforms
execve: Fix ABI change on unsized binaries

We need to adjust by the load page *after* we have checked for zero.
trs80: Check the PV flag not C on 8bit dec
ubee: check the right flag on dec b for the crtc loop.
execve: handle null files

When given an empty file execve was doing a bmap and trying to load block
-1 from the disk. Catch the empty file case earlier and error it.
crt0: set the load page to 1

Probably fcc binman should do the needed magic for such things
Merge remote-tracking branch 'alan/master' into toupstream
Kernel: Useful debug routines for Z180 (commented out)
Kernel: Bug fix -- bankfixed pagemap_realloc() check was too strict