SDL_rtf: cmake: make cmake installation folder configurable

From 08d65fc304b3c9d95a46c3810b2a33439ac5300e Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Thu, 20 Oct 2022 00:19:30 +0200
Subject: [PATCH] cmake: make cmake installation folder configurable

---
 CMakeLists.txt | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3ef85ea..025eb50 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -170,13 +170,14 @@ if(SDL2RTF_INSTALL)
     )
 
     if(WIN32 AND NOT MINGW)
-        set(PKG_PREFIX "cmake")
+        set(SDLRTF_INSTALL_CMAKEDIR_DEFAULT "cmake")
     else()
-        set(PKG_PREFIX "${CMAKE_INSTALL_LIBDIR}/cmake/SDL2_rtf")
+        set(SDLRTF_INSTALL_CMAKEDIR_DEFAULT "${CMAKE_INSTALL_LIBDIR}/cmake/SDL2_ttf")
     endif()
+    set(SDLRTF_INSTALL_CMAKEDIR "${SDLRTF_INSTALL_CMAKEDIR_DEFAULT}" CACHE STRING "Location where to install SDL2_rtfConfig.cmake")
 
     configure_package_config_file(SDL2_rtfConfig.cmake.in SDL2_rtfConfig.cmake
-        INSTALL_DESTINATION "${PKG_PREFIX}"
+        INSTALL_DESTINATION "${SDLRTF_INSTALL_CMAKEDIR}"
     )
     write_basic_package_version_file("${PROJECT_BINARY_DIR}/SDL2_rtfConfigVersion.cmake"
         VERSION ${FULL_VERSION}
@@ -186,13 +187,13 @@ if(SDL2RTF_INSTALL)
         FILES
             "${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtfConfig.cmake"
             "${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtfConfigVersion.cmake"
-        DESTINATION ${PKG_PREFIX}
+        DESTINATION ${SDLRTF_INSTALL_CMAKEDIR}
         COMPONENT devel
     )
     install(EXPORT SDL2_rtfTargets
         FILE SDL2_rtf-${sdl2_rtf_install_name_infix}-targets.cmake
         NAMESPACE SDL2_rtf::
-        DESTINATION "${PKG_PREFIX}"
+        DESTINATION "${SDLRTF_INSTALL_CMAKEDIR}"
         COMPONENT devel
     )