boards: nxp: mimxrt10xx: fix non-optimal sector distribution

- Optimize slot sizes for MCUBoot swap move algorithm
  for mimxrt1010/15/20/24/40/50/60/64 boards.
- Save up to 64 wasted sectors.
- Use DT_SIZE_K/M macros for slot sizes.
- Fix partition size errors.
- Limit mcuboot max size to 128KB (was 256KB).

Signed-off-by: Andrej Butok <andrey.butok@nxp.com>