MdeModulePkg:Fix the bug the incorrect change of StrCpyS function

MdeModulePkg:Fix the bug the incorrect change of StrCpyS function

The pointer to the destination string changed,the max length also changed.Previous change neglect this point.
And base on the code logic,we can use StrCatS to replace StrCpyS.Now this patch is to fix this bug.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18497 6f19259b-4bc3-4df7-8a09-765794883524