sdl12-compat: Install sdl.m4 to target dir instead of full dir

SDL Commits
1 
From 216d766c5bd6350c30393226ab8e4a8d14d5d0b3 Mon Sep 17 00:00:00 2001
From: Petar Popovic <[EMAIL REDACTED]>
Date: Thu, 30 Oct 2025 23:05:50 +0100
Subject: [PATCH] Install sdl.m4 to target dir instead of full dir

---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index bf355079e..f4c83332e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -243,7 +243,7 @@ if(SDL12DEVEL)
     install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libSDL${SOPOSTFIX}${SOEXT} DESTINATION "${CMAKE_INSTALL_LIBDIR}")
   endif()
 
-  install(FILES "${CMAKE_CURRENT_SOURCE_DIR}/sdl.m4" DESTINATION "${CMAKE_INSTALL_FULL_DATAROOTDIR}/aclocal")
+  install(FILES "${CMAKE_CURRENT_SOURCE_DIR}/sdl.m4" DESTINATION "${CMAKE_INSTALL_DATAROOTDIR}/aclocal")
 endif()
 
 if(STATICDEVEL AND SDL12DEVEL)