drm/imagination: remove unnecessary header include path

drivers/gpu/drm/imagination/ includes local headers with the double-quote
form (#include "...").

Hence, the header search path addition is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Matt Coster <matt.coster@imgtec.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250210102352.1517115-1-masahiroy@kernel.org


Signed-off-by: Matt Coster <matt.coster@imgtec.com>