Switch to using meson b_lto option (#5197)

lib/const.rb

 # Defines common constants used in different parts of crew
 
-CREW_VERSION = '1.7.5'
+CREW_VERSION = '1.7.6'
 
 ARCH_ACTUAL = `uname -m`.strip
 # This helps with virtualized builds on aarch64 machines
@@ -69,7 +69,7 @@ end
 
 CREW_OPTIONS = "--prefix=#{CREW_PREFIX} --libdir=#{CREW_LIB_PREFIX} --mandir=#{CREW_MAN_PREFIX} --build=#{CREW_BUILD} --host=#{CREW_BUILD} --target=#{CREW_BUILD}"
 CREW_MESON_OPTIONS = "-Dprefix=#{CREW_PREFIX} -Dlibdir=#{CREW_LIB_PREFIX} -Dmandir=#{CREW_MAN_PREFIX} -Dbuildtype=release -Dc_args='-fuse-ld=lld -pipe' -Dcpp_args='-fuse-ld=lld -pipe'"
-CREW_MESON_LTO_OPTIONS = "-Dprefix=#{CREW_PREFIX} -Dlibdir=#{CREW_LIB_PREFIX} -Dmandir=#{CREW_MAN_PREFIX} -Dbuildtype=release   -Dcpp_args='-flto -fuse-ld=gold -pipe' -Dcpp_link_args='-flto' -Dc_args='-flto -fuse-ld=gold -pipe' -Dc_link_args='-flto'"
+CREW_MESON_LTO_OPTIONS = "-Dprefix=#{CREW_PREFIX} -Dlibdir=#{CREW_LIB_PREFIX} -Dmandir=#{CREW_MAN_PREFIX} -Dbuildtype=release -Db_lto=true -Dcpp_args='-fuse-ld=gold -pipe' -Dc_args='-fuse-ld=gold -pipe'"
 
 # Cmake sometimes wants to use LIB_SUFFIX to install libs in LIB64, so specify such for x86_64
 # This is often considered deprecated. See discussio at https://gitlab.kitware.com/cmake/cmake/-/issues/18640