CMake: Avoid CMAKE_FIND_REQUIRED (#766)

Author: FtZPetruska

prboom2/cmake/DsdaDependencies.cmake

@@ -1,12 +1,7 @@
 include_guard()
 
 if(STRICT_FIND)
-  set(dsda_strict_keyword)
-  if(CMAKE_VERSION VERSION_GREATER_EQUAL 4.1)
-    set(CMAKE_FIND_REQUIRED ON)
-  else()
-    set(dsda_strict_keyword REQUIRED)
-  endif()
+  set(dsda_strict_keyword REQUIRED)
 endif()
 
 add_library(dsda_dependencies INTERFACE IMPORTED)