[packages/fzf] do not rely on uname -m to determine target arch; add more arm variants

[Elan Ruusamäe]

On 22.12.2020 00:34, atler wrote:

> -ExclusiveArch:	%{x8664} armv5l armv6l armv7l armv8l aarch64 ppc64le
> +ExclusiveArch:	%{x8664} armv5l armv5tel armv5tejl armv6l armv6hl armv7l armv7hl armv7hnl armv8l armv8hll armv8hnl armv8hcnl aarch64 ppc64le
isn't it about time to add %{arm} macro? or at least %{arm6} %{arm7} 
%{arm8} ?