UPSTREAM: drm/i915/display: Use int type for entry_setup_frames

entry_setup_frames variable is defined as u8. However, the
function call intel_psr_entry_setup_frames() can return
negative error code. There is a type mismatch here, so let's
switch to use int here as well.

Fixes: 2b981d57 ("drm/i915/display: Support PSR entry VSC packet to be transmitted one frame earlier")

Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231116090512.480373-1-mika.kahola@intel.com


(cherry picked from commit 2bb7a27b)

BUG=b:308455498
TEST=Verify Asus PG32UQXR 4K160 mode on Rex using Big Joiner

Change-Id: I8ca557cdb3a1a91ff8e9b0fc41e21d132ed066ff
Signed-off-by: Rakshith M O <rakshith.m.o@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/5803703


Reviewed-by: Sean Paul <sean@poorly.run>
Reviewed-by: Manasi Navare <navaremanasi@chromium.org>
Signed-off-by: Hubert Mazur <hmazur@google.com>