pa.c (output_function_epilogue): Perform an early %r2 restore even if actual_fsize...

pa.c (output_function_epilogue): Perform an early %r2 restore even if actual_fsize is zero.

        * pa.c (output_function_epilogue): Perform an early %r2 restore
        even if actual_fsize is zero.  This can happen if %r2 is used
        as a temporary in a leaf function.

        * pa.c (compute_frame_size): Update to take into account
        register which are no longer known to the compiler.
        (output_function_prologue): Likewise.
        (output_function_epilogue): Likewise.
        (output_arg_descriptor): Likewise.

From-SVN: r3658