accel/tcg: Add TCGCPUOps.tlb_fill_align

accel/tcg: Add TCGCPUOps.tlb_fill_align

Add a new callback to handle softmmu paging.  Return the page
details directly, instead of passing them indirectly to
tlb_set_page.  Handle alignment simultaneously with paging so
that faults are handled with target-specific priority.

Route all calls of the two hooks through a tlb_fill_align
function local to cputlb.c.

As yet no targets implement the new hook.
As yet cputlb.c does not use the new alignment check.

Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>