<memory.h> declares the memory functions of <string.h>, such as
memcpy() and memset(). It is not in POSIX, but glibc, musl and newlib
provide it, and some programs still include it. On NuttX they failed:
fatal error: memory.h: No such file or directory
Add it. It only includes <string.h>.
Assisted-by: Claude Code:claude-opus-5-5
Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>