Fix clamping issue

* Numeric limits report the lowest and highest finite values
  of F16 and BF16 to be 0 which disables testing of all F16
  and BF16 kernels with clamping.
* Update numeric limits to have the correct limits.
* Update numeric limits to make sure compilation error when
  a type is not supported.

Signed-off-by: Viet-Hoa Do <viet-hoa.do@arm.com>

Reviewed-by: Viet-Hoa Do <viet-hoa.do@arm.com>
Reviewed-by: Anton Bondarenko <anton.bondarenko@arm.com>
Approved-by: Anton Bondarenko <anton.bondarenko@arm.com>