Fix `size` type in __hipRegisterVar
Fix `size` type in __hipRegisterVar

Change-Id: I6b667600ae8f133583b768ab963318882b84179f

ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP