cmake: rename option BUILD_DOCUMENTATION

CMakeLists.txt

@@ -12,10 +12,10 @@ project(
 )
 
 option(BUILD_TESTING "Build tests" ON)
-option(BUILD_DOCUMENTATION "Build documentation" OFF)
 
 option(MTIME_ENABLE_FORTRAN_HL "Enable the high-level Fortran interface" ON)
 option(MTIME_BUILD_EXAMPLES "Build examples" ON)
+option(MTIME_BUILD_DOCS "Build documentation" OFF)
 
 list(APPEND CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/cmake")
 
@@ -39,7 +39,7 @@ if(MTIME_BUILD_EXAMPLES)
   add_subdirectory(examples)
 endif()
 
-if(BUILD_DOCUMENTATION)
+if(MTIME_BUILD_DOCS)
   add_subdirectory(doc)
 endif()