removed legacy cmake libsdir entry (#24813)

(cherry picked from commit 60e813df6b)

cmake/platform/unix/settings.cmake

@@ -4,12 +4,6 @@ if( NOT CONF_DIR )
   message(STATUS "UNIX: Using default configuration directory")
 endif()
 
-# set default library directory
-if( NOT LIBSDIR )
-  set(LIBSDIR ${CMAKE_INSTALL_PREFIX}/lib)
-  message(STATUS "UNIX: Using default library directory")
-endif()
-
 # configure uninstaller
 configure_file(
   "${CMAKE_SOURCE_DIR}/cmake/platform/cmake_uninstall.in.cmake"

cmake/showoptions.cmake

@@ -10,7 +10,6 @@ message("")
 
 message("* Install core to        : ${CMAKE_INSTALL_PREFIX}")
 if( UNIX )
-  message("* Install libraries to   : ${LIBSDIR}")
   message("* Install configs to     : ${CONF_DIR}")
 endif()
 message("")

doc/UnixInstall.txt

@@ -43,7 +43,6 @@ flags like
     CMAKE_INSTALL_PREFIX    Set installation directory
     NOJEM                   Do not build with jemalloc (advanced users only)
     CONF_DIR                Set path as default configuration directory
-    LIBSDIR                 Set path as default library directory
     CMAKE_C_FLAGS           Set C_FLAGS for compile (advanced users only)
     CMAKE_CXX_FLAGS         Set CXX_FLAGS for compile (advanced users only)
     CMAKE_BUILD_TYPE        Set build type - the supported modes are: