Turn VCREDIST into a cache variable

.github/workflows/windows.yml

@@ -104,6 +104,7 @@ jobs:
         -D OPENMW_USE_SYSTEM_SQLITE3=OFF
         -D OPENMW_USE_SYSTEM_YAML_CPP=OFF
         -D OPENMW_LTO_BUILD=ON
+        ${{ inputs.package && format('-D "VCREDIST64={0}/vc_redist.x64.exe"', env.VCToolsRedistDir) || '' }}
 
     - name: Build OpenMW
       run: cmake --build ${{ github.workspace }}/build
@@ -116,9 +117,7 @@ jobs:
 
     - name: Ensure DLLs end up in the build dir
       if: ${{ inputs.package }}
-      run: |
-        cp "${{ env.VCToolsRedistDir }}/vc_redist.x64.exe" "${{ github.workspace }}/build"
-        echo "dlldir=${{ github.workspace }}/build" >> $env:GITHUB_ENV
+      run: echo "dlldir=${{ github.workspace }}/build" >> $env:GITHUB_ENV
 
     - name: Copy missing DLLs
       run: |

CMakeLists.txt

@@ -1006,13 +1006,13 @@ elseif(NOT APPLE)
         SET(CPACK_NSIS_MUI_UNIICON "${OpenMW_SOURCE_DIR}/files/windows/openmw.ico")
         SET(CPACK_PACKAGE_ICON "${OpenMW_SOURCE_DIR}\\\\files\\\\openmw.bmp")
 
-        SET(VCREDIST32 "${OpenMW_BINARY_DIR}/vcredist_x86.exe")
+        SET(VCREDIST32 "${OpenMW_BINARY_DIR}/vcredist_x86.exe" CACHE FILEPATH "Path to vcredist_x86.exe")
         if(EXISTS ${VCREDIST32})
             INSTALL(FILES ${VCREDIST32} DESTINATION "redist")
             SET(CPACK_NSIS_EXTRA_INSTALL_COMMANDS "ExecWait '\\\"$INSTDIR\\\\redist\\\\vcredist_x86.exe\\\" /q /norestart'" )
         endif(EXISTS ${VCREDIST32})
 
-        SET(VCREDIST64 "${OpenMW_BINARY_DIR}/vcredist_x64.exe")
+        SET(VCREDIST64 "${OpenMW_BINARY_DIR}/vcredist_x64.exe" CACHE FILEPATH "Path to vcredist_x64.exe")
         if(EXISTS ${VCREDIST64})
             INSTALL(FILES ${VCREDIST64} DESTINATION "redist")
             SET(CPACK_NSIS_EXTRA_INSTALL_COMMANDS "ExecWait '\\\"$INSTDIR\\\\redist\\\\vcredist_x64.exe\\\" /q /norestart'" )