ARM archs prior to ARMv4t deprecated in GCC6

[Rin Okuyama <rokuyama%rk.phys.keio.ac.jp@localhost>]

Hi,

I've found that support for ARM architectures prior to ARMv4t has been
deprecated in GCC6:

https://gcc.gnu.org/gcc-6/changes.html#arm

> Support for revisions of the ARM architecture prior to ARMv4t has been
> deprecated and will be removed in a future GCC release. The -mcpu and
> -mtune values that are deprecated are: arm2, arm250, arm3, arm6,
> arm60, arm600, arm610, arm620, arm7, arm7d, arm7di, arm70, arm700,
> arm700i, arm710, arm720, arm710c, arm7100, arm7500, arm7500fe, arm7m,
> arm7dm, arm7dmi, arm8, arm810, strongarm, strongarm110, strongarm1100,
> strongarm1110, fa526, fa626. The value arm7tdmi is still supported.
> The values of -march that are deprecated are: armv2,armv2a,armv3,
> armv3m,armv4.

Many ARM-based ports will suffer severely if it is removed. It has not
been removed in GCC7 yet. I wonder if someone could take care of it...

Thanks,
Rin