Expose the availability of the BFloat16 (BF16) format support in the CPUs.
BF16 is a new 16-bit floating point format different from the half
precision format defined by the IEEE-754-2008.
BF16 extensions add support for new instructions for both FP/SIMD and SVE.
Advertise these features individually to the userspace via ELF HWCAP.
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: linux-doc@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>