MdePkg/BaseLib: Enhance the return value for string to uint functions

MdePkg/BaseLib: Enhance the return value for string to uint functions

For the following 8 APIs in MdePkg/BaseLib:
[Ascii]StrDecimalToUintn
[Ascii]StrDecimalToUint64
[Ascii]StrHexToUintn
[Ascii]StrHexToUint64

They will ASSERT for DEBUG build when the input string exceeds the range
of UINTN/UINT64. However, for RELEASE build, incorrect value will be
returned.

This commit refines those APIs to direcly call their enhanced counterparts
(with trailing 'S' in API names) so as to remove those exceed-range ASSERT
checks and to make those APIs to return MAX_UINTN/MAX_UINT64 instead.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>