Driver code used to map memory for DMA transfer even if host doesn't support DMA. This is causing memory corruption when driver transfers data using PIO. This change refactors the code to skip call to PciIo->Map for non DMA transfers. Cc: Hao A Wu <hao.a.wu@intel.com> Cc: Marcin Wojtas <mw@semihalf.com> Cc: Zhichao Gao <zhichao.gao@intel.com> Cc: Liming Gao <liming.gao@intel.com> Signed-off-by: Mateusz Albecki <mateusz.albecki@intel.com> Tested-by: Hao A Wu <hao.a.wu@intel.com> Reviewed-by: Hao A Wu <hao.a.wu@intel.com>