Bump the linux-mainline to the 5.17 release. This means we are also
dropping the old SiFive U540 PCIe patches as they are no longer
maintained and the board is rarley used.
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This patch does the following:
- Update the current linux-mainline_5.1 recipe to AUTOREV from the
stable branch
- Use the linux-mainline_5.1 by default for the HiFive Unleashed
- Remove the older linux-riscv_5.0 recipe
- Rename the common include to linux-mainline-common.inc
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>