LTO: consistently accept -fwhopr* and -flto* for GCC. * libltdl/config/ltmain.m4sh (func_mode_link): Accept -fwhopr*. * libltdl/m4/libtool.m4 (_LT_SYS_HIDDEN_LIBDEPS): Also match -flto*. Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>