Buildbot changes to allow out-of-tree builds (#11180)

* Do proper out-of-tree builds with buildbot
* Don't write to bin/ for cross builds
     * This allows safely building multiple builds from the same source dir, e.g. with the buildbot.
* Disable Gettext (by default) and Freetype (entirely) for server builds

src/CMakeLists.txt

@@ -55,7 +55,7 @@ if(NOT USE_CURL)
 endif()
 
 
-option(ENABLE_GETTEXT "Use GetText for internationalization" TRUE)
+option(ENABLE_GETTEXT "Use GetText for internationalization" ${BUILD_CLIENT})
 set(USE_GETTEXT FALSE)
 
 if(ENABLE_GETTEXT)
@@ -120,13 +120,13 @@ endif()
 option(ENABLE_FREETYPE "Enable FreeType2 (TrueType fonts and basic unicode support)" TRUE)
 set(USE_FREETYPE FALSE)
 
-if(ENABLE_FREETYPE)
+if(BUILD_CLIENT AND ENABLE_FREETYPE)
 	find_package(Freetype)
 	if(FREETYPE_FOUND)
 		message(STATUS "Freetype enabled.")
 		set(USE_FREETYPE TRUE)
 	endif()
-endif(ENABLE_FREETYPE)
+endif()
 
 option(ENABLE_CURSES "Enable ncurses console" TRUE)
 set(USE_CURSES FALSE)
@@ -526,8 +526,11 @@ if(USE_CURL)
 endif()
 
 
-set(EXECUTABLE_OUTPUT_PATH "${CMAKE_SOURCE_DIR}/bin")
-
+# When cross-compiling assume the user doesn't want to run the executable anyway,
+# otherwise place it in <source dir>/bin/ since Minetest can only run from there.
+if(NOT CMAKE_CROSSCOMPILING)
+	set(EXECUTABLE_OUTPUT_PATH "${CMAKE_SOURCE_DIR}/bin")
+endif()
 
 if(BUILD_CLIENT)
 	add_executable(${PROJECT_NAME} ${client_SRCS} ${extra_windows_SRCS})