drm/xe/gsc: Fix BO leak on error in query_compatibility_version()

drm/xe/gsc: Fix BO leak on error in query_compatibility_version()

When xe_gsc_read_out_header() fails, query_compatibility_version()
returns directly instead of jumping to the out_bo label. This skips
the xe_bo_unpin_map_no_vm() call, leaving the BO pinned and mapped
with no remaining reference to free it.

Fix by using goto out_bo so the error path properly cleans up the BO,
consistent with the other error handling in the same function.

Fixes: 0881cbe04077 ("drm/xe/gsc: Query GSC compatibility version")
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patch.msgid.link/20260417163308.3416147-1-shuicheng.lin@intel.com
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>