[LyX/master] Cmake build: Replace deprecated use of exec_program() command

[Kornel Benko]

commit 3fb2cef778e7a7af1f60f2867a78440e34855a65
Author: Kornel Benko <kornel at lyx.org>
Date:   Mon May 25 12:34:50 2026 +0200

    Cmake build: Replace deprecated use of exec_program() command
---
 development/cmake/modules/PCHSupport_26.cmake | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/development/cmake/modules/PCHSupport_26.cmake b/development/cmake/modules/PCHSupport_26.cmake
index 81064637c7..a1c32371a9 100644
--- a/development/cmake/modules/PCHSupport_26.cmake
+++ b/development/cmake/modules/PCHSupport_26.cmake
@@ -12,9 +12,9 @@
 
 IF(CMAKE_COMPILER_IS_GNUCXX)
 
-    EXEC_PROGRAM(
-    	${CMAKE_CXX_COMPILER}  
-        ARGS 	${CMAKE_CXX_COMPILER_ARG1} -dumpversion 
+    execute_process(
+    	COMMAND ${CMAKE_CXX_COMPILER}  
+        	${CMAKE_CXX_COMPILER_ARG1} -dumpversion 
         OUTPUT_VARIABLE gcc_compiler_version)
     #MESSAGE("GCC Version: ${gcc_compiler_version}")
     IF(gcc_compiler_version MATCHES "4\\.[0-9]\\.[0-9]")