[offload][rtl.cpp] Add mi308x and mi350x to EnvVarConfigs (llvm#743)

Author: ronlieb

offload/plugins-nextgen/amdgpu/src/rtl.cpp

@@ -5130,6 +5130,14 @@ struct AMDGPUDeviceTy : public GenericDeviceTy, AMDGenericDeviceTy {
                                  .OMPX_XteamBlockSize = 512,
                                  .OMPX_XTeamReductionOccupancyBasedOpt = false,
                                  .OMPX_AdjustNumTeamsForXteamRedSmallBlockSize=1}},
+                      {"MI308X", {.OMPX_UseMultipleSdmaEngines = true,
+                                 .OMPX_XteamBlockSize = 256,
+                                 .OMPX_XTeamReductionOccupancyBasedOpt = true,
+                                 .OMPX_AdjustNumTeamsForXteamRedSmallBlockSize=0}},
+                      {"MI350X", {.OMPX_UseMultipleSdmaEngines = true,
+                                 .OMPX_XteamBlockSize = 512,
+                                 .OMPX_XTeamReductionOccupancyBasedOpt = false,
+                                 .OMPX_AdjustNumTeamsForXteamRedSmallBlockSize=1}},
                       {"MI355X", {.OMPX_UseMultipleSdmaEngines = true,
                                  .OMPX_XteamBlockSize = 512,
                                  .OMPX_XTeamReductionOccupancyBasedOpt = false,