arch/arm: add option to use *eabihf tuples

Toolchains that use the hard-float ABI now are to be denoted by a tuple
ending in *eabihf, while the prevbious *eabi is now an indication that
the toolchain uses the softfloat ABI.

This is purely a cosmetic thing, for distros to differentiate their
hardfloat-ABI ports from their softfloat-ABI ports.

(note: softfloat ABI does not mean that it is using softfloats; it can
be using hardfloat instructions, but using the softfloat ABI).

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

# Super-H specific configuration file

## select ARCH_SUPPORTS_32

## select ARCH_DEFAULT_32

## select ARCH_USE_MMU

## select ARCH_SUPPORTS_BOTH_ENDIAN

## select ARCH_DEFAULT_LE

##

## help The Super-H architecture, as defined by:

## help     http://www.renesas.com/fmwk.jsp?cnt=superh_family_landing.jsp&fp=/products/mpumcu/superh_family/