CMake: Simplify test setup.

* Enable C++11 for test_potassco_opts and reduce duplication in cmake
  test configuration.

tests/CMakeLists.txt

@@ -7,15 +7,7 @@ set(test_lp
 	main.cpp
 )
 add_executable(test_potassco_lp ${test_lp})
-target_link_libraries(test_potassco_lp libpotassco)
-target_include_directories(test_potassco_lp	 PRIVATE
-	$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
-)
-set_target_properties(test_potassco_lp PROPERTIES
-	CXX_STANDARD 11
-	CXX_EXTENSIONS OFF
-	CXX_STANDARD_REQUIRED YES
-)
+
 set(test_opts
 	test_application.cpp
 	test_options.cpp
@@ -24,12 +16,18 @@ set(test_opts
 )
 
 add_executable(test_potassco_opts ${test_opts})
-target_link_libraries(test_potassco_opts libpotassco)
-target_include_directories(test_potassco_opts PRIVATE
-	$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
-)
+
+foreach(target test_potassco_lp test_potassco_opts)
+	message(STATUS "Processing ${target}")
+	target_link_libraries(${target} libpotassco)
+	target_include_directories(${target} PRIVATE $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>)
+	set_target_properties(${target} PROPERTIES
+		CXX_STANDARD 11
+		CXX_EXTENSIONS OFF
+		CXX_STANDARD_REQUIRED YES
+		FOLDER test
+	)
+endforeach()
 
 add_test(NAME test_lp	COMMAND test_potassco_lp)
 add_test(NAME test_opts COMMAND test_potassco_opts)
-set_target_properties(test_potassco_lp	 PROPERTIES FOLDER test)
-set_target_properties(test_potassco_opts PROPERTIES FOLDER test)