Some DMAbuf types don't properly implement MAP_PRIVATE as it requires
copy-on-write support. As we don't need to write to these buffers, we
can switch to MAP_SHARED instead, making it work reliably on current
kernels without having any drawbacks in this context.
Tested and confirmed with libcamera software ISP on Thinkpad X13 with
an arm processor.
Bug: webrtc:42225999
Change-Id: Ic47b8c90456cccf3742e8274945dbd64fb8aac6d
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/354623
Commit-Queue: Jan Grulich <grulja@gmail.com>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#42484}
025d69b4d0