[cmake] cmake_uninstall.cmake.in: Use EXECUTE_PROCESS() instead of EX…

…EC_PROGRAM().

EXECUTE_PROCESS() has been around since at least 3.0, and EXEC_PROGRAM()
is deprecated as of 3.28:

CMake Warning (dev) at cmake/cmake_uninstall.cmake:12 (EXEC_PROGRAM):
  Policy CMP0153 is not set: The exec_program command should not be called.
  Run "cmake --help-policy CMP0153" for policy details.  Use the cmake_policy
  command to set the policy and suppress this warning.

  Use execute_process() instead.

cmake/cmake_uninstall.cmake.in

@@ -1,23 +1,22 @@
 # Reference: https://cmake.org/Wiki/RecipeAddUninstallTarget
 IF(NOT EXISTS "@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt")
-  MESSAGE(FATAL_ERROR "Cannot find install manifest: @CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt")
+	MESSAGE(FATAL_ERROR "Cannot find install manifest: @CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt")
 ENDIF(NOT EXISTS "@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt")
 
 FILE(READ "@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt" files)
 STRING(REGEX REPLACE " " ";" files "${files}")
 STRING(REGEX REPLACE "\n" ";" files "${files}")
 FOREACH(file ${files})
-  MESSAGE(STATUS "Uninstalling $ENV{DESTDIR}${file}")
-  IF(EXISTS "$ENV{DESTDIR}${file}")
-    EXEC_PROGRAM(
-      "@CMAKE_COMMAND@" ARGS "-E remove $ENV{DESTDIR}${file}"
-      OUTPUT_VARIABLE rm_out
-      RETURN_VALUE rm_retval
-      )
-    IF(NOT "${rm_retval}" STREQUAL 0)
-      MESSAGE(FATAL_ERROR "Problem when removing $ENV{DESTDIR}${file}")
-    ENDIF(NOT "${rm_retval}" STREQUAL 0)
-  ELSE(EXISTS "$ENV{DESTDIR}${file}")
-    MESSAGE(STATUS "File $ENV{DESTDIR}${file} does not exist.")
-  ENDIF(EXISTS "$ENV{DESTDIR}${file}")
+	MESSAGE(STATUS "Uninstalling $ENV{DESTDIR}${file}")
+	IF(EXISTS "$ENV{DESTDIR}${file}")
+		EXECUTE_PROCESS(COMMAND "@CMAKE_COMMAND@" -E remove "$ENV{DESTDIR}${file}"
+			OUTPUT_VARIABLE rm_out
+			RESULT_VARIABLE rm_retval
+			)
+		IF(NOT "${rm_retval}" STREQUAL 0)
+			MESSAGE(FATAL_ERROR "Problem when removing $ENV{DESTDIR}${file}")
+		ENDIF(NOT "${rm_retval}" STREQUAL 0)
+	ELSE(EXISTS "$ENV{DESTDIR}${file}")
+		MESSAGE(STATUS "File $ENV{DESTDIR}${file} does not exist.")
+	ENDIF(EXISTS "$ENV{DESTDIR}${file}")
 ENDFOREACH(file)