Decode mtd ioctls

Decode mtd ioctls

I got tired of figuring out mtd structures (which show up a lot
in the embedded space), so add decoders for those ioctls.

* defs.h (mtd_ioctl): New prototype.
(print_loff_t): Likewise.
* io.c (print_loff_t): Delete static keyword
* ioctl.c (ioctl_decode): Call mtd_ioctl when code is 'M'.
* Makefile.am (strace_SOURCES): Add mtd.c.
(EXTRA_DIST): Add linux/mtd-abi.h.
* mtd.c: New file.
* linux/mtd-abi.h: New file.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>