feature-arm-vfp.inc: Allow hard-float on newer simd targets

feature-arm-vfp.inc: Allow hard-float on newer simd targets

Currently hard-float is dependency upon the special TUNE_CCARGS_MFPU which
contains custom -mfpu= values.  However, newer 32-bit architectures like
cortex-r52 use 'simd' instead.  There is no 'simd' entry for -mfpu=
according to the GCC manual, it's more or less automatic based on the
cpu settings.

Add this as an exception to the TUNE_CCARGS_FLOAT setting of hard or softfp.

Signed-off-by: Mark Hatle <mark.hatle@amd.com>
Signed-off-by: Mark Hatle <mark.hatle@kernel.crashing.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>