boot to display "Booting the kernelel...done" instead of "Booting
the kernel".
Removed save and restore of BIOS memory. kzipped kernels haven't
ever overlaid the BIOS memory.
serial_putchar() always hung if it was called and the serial port existed,
so booting with -h hung when the above bug was fixed. Previously, setting
-h did nothing but -h was sometimes the default due to the stack garbage
bug.