a) Fix a number of missing instances of DZ and ZWORD.
b) NASM would crash if TIMES was used on an instruction which varies
in size, e.g. JMP. Fix this by moving the handling of TIMES at a
higher level, so we generate the instruction "de novo" for each
iteration. The exception is INCBIN, so we can avoid reading the
included file over and over.
c) When using the RESx instructions, just fold TIMES into the reserved
space size; there is absolutely no point to iterate over it.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>