Tests: Move LINK_SEARCH_{START,END}_STATIC case to dedicated test

The test case added to RunCMake.set_property by commit 675ef165 (Allow
LINK_SEARCH_{START,END}_STATIC props to have default values, 2015-08-07)
is not a test of the set_property command and so belongs in its own test
case.  Create a new RunCMake.LinkStatic test to cover cases related to
static linking.

While at it, simplify the LINK_SEARCH_STATIC test case to enable only C.

Tests/RunCMake/CMakeLists.txt

@@ -139,6 +139,7 @@ add_RunCMake_test(GeneratorToolset)
 add_RunCMake_test(GNUInstallDirs)
 add_RunCMake_test(TargetPropertyGeneratorExpressions)
 add_RunCMake_test(Languages)
+add_RunCMake_test(LinkStatic)
 add_RunCMake_test(ObjectLibrary)
 add_RunCMake_test(Swift)
 add_RunCMake_test(TargetObjects)

Tests/RunCMake/LinkStatic/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.3)
+project(${RunCMake_TEST} NONE)
+include(${RunCMake_TEST}.cmake)

Tests/RunCMake/LinkStatic/LINK_SEARCH_STATIC.cmake

@@ -1,4 +1,4 @@
-project(LinkSearchStatic)
+enable_language(C)
 
 set(CMAKE_LINK_SEARCH_START_STATIC ON)
 add_executable(LinkSearchStartStaticInit1 LinkStatic.c)

Tests/RunCMake/LinkStatic/RunCMakeTest.cmake

@@ -0,0 +1,3 @@
+include(RunCMake)
+
+run_cmake(LINK_SEARCH_STATIC)

Tests/RunCMake/set_property/RunCMakeTest.cmake

@@ -1,4 +1,3 @@
 include(RunCMake)
 
 run_cmake(LINK_LIBRARIES)
-run_cmake(LINK_SEARCH_STATIC)