drm/xe: Remove leftover pxp comment

Not being able to initialize pxp is fatal if the platform is expected to
have it. Update comment after commit 9c9dc9ba4a00 ("drm/xe/pxp: Fail the
load if PXP fails to initialize").

Cc: Daniele Ceraolo Spurio <[e-mail]>
Reviewed-by: Daniele Ceraolo Spurio <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]
Signed-off-by: Lucas De Marchi <[e-mail]>

drivers/gpu/drm/xe/xe_device.c

···
 	if (err)
 		goto err_fini_oa;
 
-	/* A PXP init failure is not fatal */
 	err = xe_pxp_init(xe);
 	if (err)
 		goto err_fini_display;