[lld] r249146 - Allow -soname arg in addition to -soname=arg

[Rafael Espíndola via llvm-commits]

>  def alias_soname : Separate<["-"], "h">, Alias<soname>;
> +def alias_snoame : Separate<["-"], "soname">, Alias<soname>;
>
snoame?

Cheers,
Rafael