Update LoadHIP to respect HIP SDK 6.1 on Windows

Author: m-gallus

cmake/public/LoadHIP.cmake

@@ -530,7 +530,6 @@ endif()
     find_package_and_print_version(hipsolver REQUIRED)
 
     list(APPEND CMAKE_MODULE_PATH ${ROCM_PATH}/cmake)
-    set(HIP_PLATFORM AMD)
     find_package_and_print_version(HIP MODULE REQUIRED)
 
     find_library(PYTORCH_HIP_LIBRARIES amdhip64 HINTS ${ROCM_PATH}/lib)