Fix var CUDA_PATH_V128 in cuda128.bat file (pytorch#146906)

Followup after: pytorch#146653
This should fix upcoming CUDA 12.8 windows builds.
Issue found during pytorch-canary Windows AMI test.

Pull Request resolved: pytorch#146906
Approved by: https://github.com/malfet, https://github.com/tinglvv

Author: atalman

.ci/pytorch/windows/cuda128.bat

@@ -43,8 +43,8 @@ IF "%BUILD_VISION%" == "" (
     set NVCC_FLAGS=-D__CUDA_NO_HALF_OPERATORS__ --expt-relaxed-constexpr -gencode=arch=compute_50,code=sm_50 -gencode=arch=compute_60,code=sm_60 -gencode=arch=compute_70,code=sm_70 -gencode=arch=compute_75,code=sm_75 -gencode=arch=compute_80,code=compute_80 -gencode=arch=compute_86,code=compute_86 -gencode=arch=compute_90,code=compute_90 -gencode=arch=compute_100,code=compute_100 -gencode=arch=compute_120,code=compute_120
 )
 
-set "CUDA_PATH=%CUDA_PATH_V126%"
-set "PATH=%CUDA_PATH_V126%\bin;%PATH%"
+set "CUDA_PATH=%CUDA_PATH_V128%"
+set "PATH=%CUDA_PATH_V128%\bin;%PATH%"
 
 :optcheck
 
@@ -56,4 +56,4 @@ call  %~dp0\internal\copy.bat
 IF ERRORLEVEL 1 goto :eof
 
 call  %~dp0\internal\setup.bat
-IF ERRORLEVEL 1 goto :eof
+IF ERRORLEVEL 1 goto :eof