Confusing error message with cmake version 3.13 (or <3.16)

Client version: N/A

Server OS: Linux

Cuberite Commit id: 90ce4ed2b8ac47bd6f528815e6c21f0128e71dba



### Description

Confusing CMake warning message caused by a minor typo in [CMakeLists.txt:85](https://github.com/cuberite/cuberite/blob/a145980795a4f37ebb9857bddb7427a184bbd6dd/CMakeLists.txt#L85).



### Expected behavior

CMake output:

```

...snip...

Precompiled headers for FASTER BUILDS not enabled, upgrade to CMake 3.16 or newer!

...snip...

```



### Actual behavior

CMake output:

```

...snip...

Precompiled headers for FASTER BUILDS not enabled, upgrade to CMake 1.16 or newer!

...snip...

```



### Steps to reproduce the behavior

Configure project using a cmake version >=3.13 and <3.16



### Server log

N/A



It could be changed to something like this:

```diff

diff --git a/CMakeLists.txt b/CMakeLists.txt

index da77aed5a..e4f99d125 100644

--- a/CMakeLists.txt

+++ b/CMakeLists.txt

@@ -75,14 +75,15 @@ set_property(DIRECTORY PROPERTY VS_STARTUP_PROJECT ${CMAKE_PROJECT_NAME})

 set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES VS_DEBUGGER_WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/Server")

 

 # Enable PCH and jumbo builds on supporting CMake:

-if (CMAKE_VERSION VERSION_GREATER_EQUAL "3.16")

+set(CMAKE_PCH_VERSION_MIN "3.16")

+if (CMAKE_VERSION VERSION_GREATER_EQUAL ${CMAKE_PCH_VERSION_MIN})

        if (PRECOMPILE_HEADERS)

                target_precompile_headers(${CMAKE_PROJECT_NAME} PRIVATE src/Globals.h)

        endif()

 

        set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES UNITY_BUILD ${UNITY_BUILDS})

 else()

-       message(WARNING "Precompiled headers for FASTER BUILDS not enabled, upgrade to CMake 1.16 or newer!")

+       message(WARNING "Precompiled headers for FASTER BUILDS not enabled, upgrade to CMake ${CMAKE_PCH_VERSION_MIN} or newer!")

 endif()

 

 # Selectively disable warnings in the level where the target is created:

```

[]