ShellPkg/editor: Fix system hang when console max column > 200

ShellPkg/editor: Fix system hang when console max column > 200

EditorClearLine() assumes the console max column is less than 200.
When the max column is bigger than 200, the code incorrectly
modifies the content out side of Line buffer.
It may cause system hang or reset.

The patch changes the function to print several times when
the max column is bigger than 200.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>