* h8300-tdep.c (IS_PUSH): Refine.

    * h8300-tdep.c (IS_PUSH): Refine.
        (IS_MOVE_FP, IS_MOV_SP_FP): Accept H8/300H varaints.
        (IS_SUB4_SP, IS_SUBL_SP): New macros.
        (h8300_skip_prologue): Handle H8/300H prologue code sequences.
        (examine_prologue): Handle addresses from 0x010000 to 0xffffff
        when in H8/300H mode.  Get the return pointer's address correctly
        for the H8/300H.  Handle H8/300H prolouge code sequences.
Avoiding major breakage on the H8/300H, and on the eval board.  Jeez, did
anyone even try to debug H8/300H code with gdb in the past?!?