MdeModulePkg/EbcDebugger: Change function names

MdeModulePkg/EbcDebugger: Change function names

Change UnicodeToUpper to InternalUnicodeToUpper.
Change AsciiToUpper to InternalAsciiToUpper.
These changes are committed for bisectability, or build failure will
occur when 2/7 is applied. Because the introduced function names in
2/7 are the same as ones in EdbSupporting.c.
https://bugzilla.tianocore.org/show_bug.cgi?id=1369

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>