libcamera: base: shared_fd: Rename fd() to get()

For consistency with UniqueFD, rename the fd() function to get().
Renaming UniqueFD::get() to fd() would have been another option, but was
rejected to keep as close as possible to the std::shared_ptr<> and
std::unique_ptr<> APIs.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>

src/libcamera/mapped_framebuffer.cpp

@@ -198,7 +198,7 @@ MappedFrameBuffer::MappedFrameBuffer(const FrameBuffer *buffer, MapFlags flags)
 	std::map<int, MappedBufferInfo> mappedBuffers;
 
 	for (const FrameBuffer::Plane &plane : buffer->planes()) {
-		const int fd = plane.fd.fd();
+		const int fd = plane.fd.get();
 		if (mappedBuffers.find(fd) == mappedBuffers.end()) {
 			const size_t length = lseek(fd, 0, SEEK_END);
 			mappedBuffers[fd] = MappedBufferInfo{ nullptr, 0, length };
@@ -220,7 +220,7 @@ MappedFrameBuffer::MappedFrameBuffer(const FrameBuffer *buffer, MapFlags flags)
 	}
 
 	for (const FrameBuffer::Plane &plane : buffer->planes()) {
-		const int fd = plane.fd.fd();
+		const int fd = plane.fd.get();
 		auto &info = mappedBuffers[fd];
 		if (!info.address) {
 			void *address = mmap(nullptr, info.mapLength, mmapFlags,