The unused global variable InvalidChars is removed.
It is only used in the function IsValidCommandName which
was removed previously.
https://bugzilla.tianocore.org/show_bug.cgi?id=1066
Cc: Jaben Carsey <jaben.carsey@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: shenglei <shenglei.zhang@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>