drm/i915/uc: Fix two issues with over-size firmware files

In the case where a firmware file is too large (e.g. someone
downloaded a web page ASCII dump from github...), the firmware object
is released but the pointer is not zerod. If no other firmware file
was found then release would be called again leading to a double kfree.

Also, the size check was only being applied to the initial firmware
load not any of the subsequent attempts. So move the check into a
wrapper that is used for all loads.

Fixes: 01624116 ("drm/i915/uc: use different ggtt pin offsets for uc loads")
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Thomas Hellström" <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221221193031.687266-4-John.C.Harrison@Intel.com