libdrm: find drm.h is inside kernel tree, link to buildroot bug report.

Play with multiple -device virtio-gpu-pci

README.adoc

@@ -419,6 +419,14 @@ CONFIG_DRM_VIRTIO_GPU=y
 
 Unlike x86, `arm` and `aarch64` don't have a display device attached by default, thus the need for `virtio-gpu-pci`.
 
+It is also fun to pass the `-device` multiple times and see that multiple screens show up:
+
+....
+./run -aA -x -- -device virtio-gpu-pci
+....
+
+Multiple `/dev/dri/cardN` are also created accordingly.
+
 See also https://wiki.qemu.org/Documentation/Platforms/ARM (recently edited and corrected by yours truly... :-)).
 
 ===== Graphic mode arm VGA
@@ -3797,6 +3805,16 @@ In file included from modeset.c:40:0:
                  ^
 ....
 
+Report: https://bugs.busybox.net/show_bug.cgi?id=11056
+
+This file appears to come from the Linux kernel tree:
+
+....
+linux/include/uapi/drm/drm.h
+....
+
+e.g. for `drm_context_t`. It does appear under `out/*/build/linux-headers`, but does not show up on `target/`.
+
 libdri2 attempt:
 
 ....