Update to kernel headers v5.2.6.

Also, fix a bug in update_all.py when the syscalls file does not change.

Test: Builds and boots on a taimen.
Change-Id: If85b00daef2c176f804a0861894f5bbca9c6d5df
diff --git a/libc/kernel/uapi/linux/videodev2.h b/libc/kernel/uapi/linux/videodev2.h
index e6df45c..f77c6bd 100644
--- a/libc/kernel/uapi/linux/videodev2.h
+++ b/libc/kernel/uapi/linux/videodev2.h
@@ -210,7 +210,7 @@
 #define V4L2_PIX_FMT_RGBX444 v4l2_fourcc('R', 'X', '1', '2')
 #define V4L2_PIX_FMT_ABGR444 v4l2_fourcc('A', 'B', '1', '2')
 #define V4L2_PIX_FMT_XBGR444 v4l2_fourcc('X', 'B', '1', '2')
-#define V4L2_PIX_FMT_BGRA444 v4l2_fourcc('B', 'A', '1', '2')
+#define V4L2_PIX_FMT_BGRA444 v4l2_fourcc('G', 'A', '1', '2')
 #define V4L2_PIX_FMT_BGRX444 v4l2_fourcc('B', 'X', '1', '2')
 #define V4L2_PIX_FMT_RGB555 v4l2_fourcc('R', 'G', 'B', 'O')
 #define V4L2_PIX_FMT_ARGB555 v4l2_fourcc('A', 'R', '1', '5')