small ioremap cleanups

From: Christoph Hellwig
Date: Tue Aug 24 2021 - 05:15:18 EST

Hi Andrew,

the first patch moves a little code around the vmalloc/ioremap
boundary followed a bigger move by Nick earlier. The second
enforces non-executable mapping on ioremap just like we do
for vmap. No driver currently uses executable mappings anyway,
as they should.