media: go7007: avoid clang frame overflow warning with KASAN

clang-8 warns about one function here when KASAN is enabled, even
without the 'asan-stack' option:

drivers/media/usb/go7007/go7007-fw.c:1551:5: warning: stack frame size of 2656 bytes in function

I have reported this issue in the llvm bugzilla, but to make
it work with the clang-8 release, a small annotation is still
needed.

Link: https://bugs.llvm.org/show_bug.cgi?id=38809



Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: fix checkpatch warning]
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>