Avoid writing empty AdditionalOptions to PS3 compiler blocks

src/actions/vstudio/vs200x_vcproj.lua

@@ -320,7 +320,9 @@
 			_p(4,'UsePrecompiledHeader="%s"', iif(_ACTION > "vs2003" or cfg.flags.NoPCH, 0, 2))
 		end
 
-		_x(4,'AdditionalOptions="%s"', table.concat(buildoptions, " "))
+		if #buildoptions > 0 then
+			_x(4,'AdditionalOptions="%s"', table.concat(buildoptions, " "))
+		end
 
 		if #cfg.includedirs > 0 then
 			_x(4,'AdditionalIncludeDirectories="%s"', path.translate(table.concat(cfg.includedirs, ";")))

tests/actions/vstudio/vc200x/test_compiler_block.lua

@@ -334,7 +334,6 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				UsePrecompiledHeader="0"
-				AdditionalOptions=""
 				ProgramDataBaseFileName="$(OutDir)\MyProject.pdb"
 				DebugInformationFormat="0"
 				CompileAs="0"