Now that there is plenty of space (32 KiB) available for NOBITS
sections, we can afford using an entire page for coherent memory. In
fact, because it simplifies the code, this is a beneficial change for
loaded image (.text) size, where we are still close to the size limit.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Change-Id: I0b899dabcb162015c63b0e4aed0869569c889ed9