bump slop for twiceprecision division (#59140)

division (unlike the other intrinsics) can have table-maker dilema
problems since the true result has infinite bits. Bumping the slop for
it by 1 reduces failures from 80 in 10^10 to <1 in 10^11.

I think accepting an extra bit of inaccuracy is reasonable here (the
alternative would be to make the division do an extra loop and do some
extra extended precision, which seems unlikely to be worth it.

fixes #23497

Co-authored-by: oscarddssmith <[email protected]>

Author: oscardssmith

test/ranges.jl

@@ -230,7 +230,7 @@ end
             @test cmp_sn2(Tw(xw+yw), astuple(x+y)..., slopbits)
             @test cmp_sn2(Tw(xw-yw), astuple(x-y)..., slopbits)
             @test cmp_sn2(Tw(xw*yw), astuple(x*y)..., slopbits)
-            @test cmp_sn2(Tw(xw/yw), astuple(x/y)..., slopbits)
+            @test cmp_sn2(Tw(xw/yw), astuple(x/y)..., slopbits+1) # extra bit because division is hard
             y = rand(T)
             yw = widen(widen(y))
             @test cmp_sn2(Tw(xw+yw), astuple(x+y)..., slopbits)