Some libdecnumber headers avoid including decNumber.h or decContext.h
again by checking their header guards.  Don't.  Including them
multiple times is safe, and the compiler can do it efficiently.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Consistent with other libraries in QEMU, the libdecnumber header files were
placed in include/libdecnumber, separate from the C code.  This is different
from the original libdecnumber source, where they were co-located.

Change the libdecnumber source code so that it reflects this split.  Specifically,
modify directives of the form:

    #include "xxx.h"

to look like:

    #include "libdecnumber/xxx.h"
Signed-off-by: NTom Musta <tommusta@gmail.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

The various *Symbols.h files were not copied from the original GCC libdecnumber
library; they are not necessary for use in QEMU.  Remove all instances of

    #include "*Symbols.h"
Signed-off-by: NTom Musta <tommusta@gmail.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Add files from the libdecnumber decimal floating point library to QEMU.  The libdecnumber
library was originally part of GCC and contains code that is useful in emulating the PowerPC
decimal floating point (DFP) instructions.  This particular copy of the source comes from
GCC 4.3 and is licensed at GPLv2+.
Signed-off-by: NTom Musta <tommusta@gmail.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>