host.cmake, win9x.cmake: fetch libfixmath if missing

cmake/fetch-libfixmath.cmake

@@ -0,0 +1,8 @@
+find_path(libfixmath "CMakeLists.txt"
+    PATHS "${PROJECT_SOURCE_DIR}/libfixmath/"
+    NO_DEFAULT_PATH)
+
+if(${libfixmath} STREQUAL "libfixmath-NOTFOUND")
+    message(STATUS "Fetching submodules...")
+    execute_process(COMMAND git submodule update --init --recursive)
+endif()

cmake/host.cmake

@@ -9,4 +9,5 @@ else()
     set(cflags ${cflags} -O3)
 endif()
 
+include("${CMAKE_CURRENT_LIST_DIR}/fetch-libfixmath.cmake")
 add_subdirectory(libfixmath)

cmake/win9x.cmake

@@ -34,4 +34,5 @@ else()
     set(cflags ${cflags} -O2)
 endif()
 
+include("${CMAKE_CURRENT_LIST_DIR}/fetch-libfixmath.cmake")
 add_subdirectory(libfixmath)