FROMLIST: squashfs: Customize squashfs metadata cache size

It provides customization using module params.
In some use-cases reading metadata may take comparable time reading data
itself. Increasing the cache size in such cases helps to eliminate that
bottleneck and increase the overall performance.

BUG=b:241129066
TEST=Locally, coral-arc-r shows 3 seconds improvement in regular and
provisioning boot (5% and 8% boost). Energy reduces on 150j (3%).

(am from https://lore.kernel.org/all/20220808205822.1350030-1-khmel@google.com

)

Signed-off-by: Yury Khmel <khmel@chromium.org>
Link: https://lore.kernel.org/all/20220808205822.1350030-1-khmel@google.com/
Change-Id: I30078951fef426272b3dbc1727488579d82314e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/3806140


Reviewed-by: Suleiman Souhlal <suleiman@chromium.org>
Reviewed-by: Yusuke Sato <yusukes@chromium.org>
Signed-off-by: Richard Fung <richardfung@google.com>