Address review feedback

Author: andykaylor

clang/include/clang/CIR/Dialect/IR/CIROps.td

@@ -1290,7 +1290,7 @@ def GetGlobalOp : CIR_Op<"get_global",
     The `cir.get_global` operation retrieves the address pointing to a
     named global variable. If the global variable is marked constant, writing
     to the resulting address (such as through a `cir.store` operation) is
-    undefined. Resulting type must always be a `!cir.ptr<...>` type with the
+    undefined. The resulting type must always be a `!cir.ptr<...>` type with the
     same address space as the global variable.
 
     Example:

clang/lib/CIR/CodeGen/CIRGenModule.cpp

@@ -203,10 +203,7 @@ void CIRGenModule::emitGlobalFunctionDefinition(clang::GlobalDecl gd,
 }
 
 mlir::Operation *CIRGenModule::getGlobalValue(StringRef name) {
-  mlir::Operation *global = mlir::SymbolTable::lookupSymbolIn(theModule, name);
-  if (!global)
-    return nullptr;
-  return global;
+  return mlir::SymbolTable::lookupSymbolIn(theModule, name);
 }
 
 /// If the specified mangled name is not in the module,