(sh_expand_prologue): Clear extra_push at start.

(sh_expand_prologue): Clear extra_push at start.

(sh_expand_prologue): Clear extra_push at start.  Clear
current_function_anonymous_args if set.  Clear shiftsyms array.
(sh_expand_epilogue): Don't clear extra_push,
current_function_pretend_args_size, current_function_anonymous_args,
and shiftsyms array.

From-SVN: r8697