ERROR_EOM_OVERFLOW and ERROR_NO_DATA_DETECTED to EIO. Add mappings
for ERROR_NO_MEDIA_IN_DRIVE, ERROR_DEVICE_REQUIRES_CLEANING and
ERROR_DEVICE_DOOR_OPEN.
* fhandler.h (class fhandler_dev_raw): Drop varblkop member.
(fhandler_dev_raw::is_eom): De-virtualize.
(fhandler_dev_raw::is_eof): Ditto.
(class fhandler_dev_tape): Drop lasterr and dp member. Add mt_mtx
member. Drop all private methods formerly used by ioctl.
(fhandler_dev_tape::is_rewind_device): Use get_minor for clarity.
(fhandler_dev_tape::driveno): New method.
(fhandler_dev_tape::drive_init): New method.
(fhandler_dev_tape::clear): Remove method.
(fhandler_dev_tape::is_eom): Ditto.
(fhandler_dev_tape::is_eof): Ditto.
(fhandler_dev_tape::write_file): Ditto.
(fhandler_dev_tape::read_file): Ditto.
(fhandler_dev_tape::_lock): New method.
(fhandler_dev_tape::unlock): New method.
(fhandler_dev_tape::raw_read): New method.
(fhandler_dev_tape::raw_write): New method.
* fhandler_raw.cc (fhandler_dev_raw::is_eom): New method.
(fhandler_dev_raw::is_eof): New method.
(fhandler_dev_raw::open): Allow setting write through option by
using the O_TEXT flag as ... flag.
(fhandler_dev_raw::writebuf): Remove usage of varblkop and other
tape specific code.
(fhandler_dev_raw::raw_read): Ditto.
(fhandler_dev_raw::dup): Ditto.
* fhandler_tape.cc: Rewrite tape operations entirely. Implement
new tape driver classes mtinfo, mtinfo_drive and mtinfo_part.
Reduce fhandler_dev_tape methods to mostly just calling appropriate
mtinfo_drive methods.
(mtinfo_init): New function adding the mtinfo shared memory area.
* mtinfo.h: New file, containing the definition of the new tape
driver classes.
* shared.cc: Include mtinfo.h.
(offsets): Add entry for mtinfo shared memory area.
(memory_init): Call mtinfo_init.
* shared_info.h (shared_locations): Add SH_MTINFO shared location.
* include/cygwin/mtio.h: Change and add various comments. Add GMT_xxx
macros for new generic flags. Add MT_ST_xxx bitfield definitions
for MTSETDRVBUFFER ioctl.
* include/cygwin/version.h: Bump API minor version number.