The /dev/mem file descriptor can be closed without invalidating the
mappings so close as soon as possible.
munmap() all memory, either on error or from quit.
Signed-off-by: Steve Marple <stevemarple@googlemail.com>
Change-Id: I2b6a8365f554e332520fa77ccf076188083a932f
Reviewed-on: https://review.openocd.org/c/openocd/+/7122
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>