It can happen that the user reads an input attachment as the first use
of that attachment. In that case there are no subpass dependencies
required at all, because there could be a pipeline barrier before the
renderpass instead, and in any case we assume that dependencies with the
first subpass as a destination can be executed only once outside the
renderpass. The result is that we only do a CACHE_INVALIDATE once
before the entire renderpass, but it's actually required after each GMEM
load, because input attachments read GMEM through UCHE and those writes
to GMEM invalidate UCHE.

While we could add the missing CACHE_INVALIDATE "by hand" somehow, it
turns out it's actually just as easy to do an optimization the blob
does, where it simply doesn't patch those input attachments and reads
them directly instead. This means we can skip allocating memory in GMEM
for them entirely in some circumstances.

This fixes e.g.
dEQP-VK.api.copy_and_blit.core.resolve_image.whole_array_image.4_bit
with TU_DEBUG=forcebin.

Part-of: <!12213>