Bug#1143807: missing -many asm option by default, resulting in FTBFS bugs

Package: gcc-16-powerpc-linux-gnu
Version: 16.1.0-3cross1
Severity: normal
Tags: ftbfs

powerpc and powerpc64 flavours used to unconditionally specify -many
assembler option when invoking `as` binary.  This way, `as' accepted
mixed instructions.

For example, when building openbios for ppc, we have:

 powerpc-linux-gnu-gcc -m32 -m604 ... start.S

with previous versions of gcc, this resulted in

 as -a32 -mppc -many -mbig ...

now with gcc-16.1.0, the -many is missing:

 as -a32 -mppc -mbig ...

and `as` complains about unrecognized instructions such as clrldi,
mtmsrd, ld, std, - which are 64bits and are valid for this CPU type.

The same happens with powerpc64, which also omits -many now, so `as'
rejects other instructions, such as hrfid or nap, and there, adding
-many explicitly lets the build to continue.

I don't know if this is an intended change or not, - especially since
I know right to nothing about ppc assembly.  But it feels like it is
not intended.  On Fedora, gcc-16.1.1 does pass -many unconditionally,
as it were before.  So it feels like only debian is broken currently.

This issue breaks qemu build (#1143769).  I can work around this by
explicitly passing -Wa,-many in two places, but it feels wrong to do
that.

Thanks,

/mjt