* defs.h: if xm.h doesn't define FOPEN_RB, include "fopen-same.h",
allowing hosts with different text and binary file formats to
work.
* coffread.c (read_coff_symtab): changed calling convention and
operation - now it opens its own file with FOPEN_RB rather than
duping and fdopening the provided handle.
* dbxread.c, cplus-dem.c: #include mangling.
* exec.c: If O_BINARY isn't defined, set it to 0, call openp for
binary files oring in the right bit.
* utils.c, terminal.h, inflow.c: hackery because dos doesn't have terminals.
* remote-hms.c: cleanup to use the new remote serial stuff
* serial.h, ser-termios.c, ser-go32.c: newfiles to provide host
independent remote terminal I/O.
* remote.c: if DONT_USE_REMOTE is defined, then don't use it.
* source.c (openp): fix off by one problem removing / - can now
open a source file in the root directory with DOS.
* values.c (value_as_pointer): remove bogus address bits from
long. (unpack_long): unpack into unsigned long/short if pointer.
sun4.mh: use the ser-termios stuff
go32.mh: use the ser-go32 stuff
