drm/xe: Add assert for XE_WA() usage

It's not always safe to call XE_WA() in the driver initialization. Add a
xe_gt_assert() so this doesn't go unnoticed.

While at it, fix typo in kernel-doc about OOB workarounds.

Reviewed-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240722160815.4085605-1-lucas.demarchi@intel.com


Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>