SDL_ttf: cmake: cannot install SDL2_ttf when SDL2 is also built but not installed

SDL Commits
1 
From c643f520c22d3e6442cc7cda4026c9cd1e6e52ec Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Thu, 9 Feb 2023 20:32:13 +0100
Subject: [PATCH] cmake: cannot install SDL2_ttf when SDL2 is also built but
 not installed

---
 CMakeLists.txt | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index a3387d5..e946a16 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -42,6 +42,12 @@ else()
     set(vendored_default FALSE)
 endif()
 
+set(sdl2ttf_install_enableable ON)
+if ((TARGET SDL2 OR TARGET SDL2-static) AND SDL2_DISABLE_INSTALL)
+    # Cannot install SDL2_mixer when SDL2 is built in same built, and is not installed.
+    set(sdl2ttf_install_enableable OFF)
+endif()
+
 include(CMakeDependentOption)
 include(CMakePackageConfigHelpers)
 include(GNUInstallDirs)
@@ -51,7 +57,7 @@ option(CMAKE_POSITION_INDEPENDENT_CODE "Build static libraries with -fPIC" ON)
 option(BUILD_SHARED_LIBS "Build the library as a shared library" ON)
 
 option(SDL2TTF_SAMPLES "Build the SDL2_ttf sample program(s)" ${SDL2TTF_ROOTPROJECT})
-option(SDL2TTF_INSTALL "Enable SDL2_ttf install target" ${SDL2TTF_ROOTPROJECT})
+cmake_dependent_option(SDL2TTF_INSTALL "Enable SDL2_ttf install target" ${SDL2TTF_ROOTPROJECT} "${sdl2ttf_install_enableable}" OFF)
 option(SDL2TTF_VENDORED "Use vendored third-party libraries" ${vendored_default})
 
 # For style consistency, create a SDL2TTF_FREETYPE CMake variable. This variable is NOT configurable.