fixrsdp: add write verification.
fixrsdp: add write verification.

Verify writes to /dev/mem. Depending on kernel settings like CONFIG_STRICT_DEVMEM, writes to /dev/mem can silently fail.

Signed-off-by: Rob Vandermeulen <98a4272011663e1b10a5f6e1f789cca0b2d0d7ef@gmail.com>

u-root/u-root,u-root/u-root,u-root/u-root