winsys/i915: depends on intel_wa.h
What does this MR do and why?
winsys/i915: depends on intel_wa.h
Prevent compilation failure due to not-yet generated intel_wa header.
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/11174
Cc: mesa-stable
Signed-off-by: David Heidelberg <david.heidelberg@collabora.com>