SPIRV: Set NoPHIs property after rewriting them (#136327)

There should be no PHIs after selection, as OpPhi is used
 instead. This hopefully avoids errors in #135277.
diff --git a/llvm/lib/Target/SPIRV/SPIRVModuleAnalysis.cpp b/llvm/lib/Target/SPIRV/SPIRVModuleAnalysis.cpp
index 6e1c41d..a6482d9 100644
--- a/llvm/lib/Target/SPIRV/SPIRVModuleAnalysis.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVModuleAnalysis.cpp
@@ -2029,6 +2029,8 @@
                   {MachineOperand::CreateReg(ResTypeReg, false)});
       }
     }
+
+    MF->getProperties().set(MachineFunctionProperties::Property::NoPHIs);
   }
 }