re PR rtl-optimization/49994 (ICE: in maybe_record_trace_start, at dwarf2cfi.c:2234 with -fsched2-use-superblocks)

PR rtl-opt/49994
        * sched-init.h (struct deps_desc): Add sched_before_next_jump.
        * sched-deps.c (init_deps): Clear it.
        (deps_analyze_insn): Consume it.
        (sched_analyze_insn): Fill it.

From-SVN: r177721