A recent change added a use of xe_wa_oob.h without adding the file that
uses it to uses_generated_oob, which means xe_wa_oob.h does not get
properly generated before attempting to build the object file:

    LINK     resolve_btfids
    CC [M]  drivers/gpu/drm/xe/xe_guc_ads.o
  drivers/gpu/drm/xe/xe_guc_ads.c:10:10: fatal error: generated/xe_wa_oob.h: No such file or directory
     10 | #include <generated/xe_wa_oob.h>
        |          ^~~~~~~~~~~~~~~~~~~~~~~

After adding '$(obj)/xe_guc_ads.o' to uses_generated_oob, xe_wa_oob.h is
always generated before building the file, resulting in no errors:

    LINK     resolve_btfids
    HOSTCC  drivers/gpu/drm/xe/xe_gen_wa_oob
    GEN     xe_wa_oob.c xe_wa_oob.h
    CC [M]  drivers/gpu/drm/xe/xe_guc_ads.o

Fixes: c151ff5c ("drm/xe/lnl: Enable GuC Wa_14019882105")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240410-drm-xe-fix-xe_guc_ads-using-xe_wa_oob-v1-1-441f2d8e5d83@kernel.orgSigned-off-by: Lucas De Marchi <lucas.demarchi@intel.com>