Currently both the qemu-arm and qemu-riscv ports share a lot of code and
functionality. This commit merges the qemu-riscv port into the qemu-arm
port. The only real differences between the two are the toolchains used to
build the code, and the initialisation/startup framework. Everything else
is pretty much the same, so this brings the following benefits:
- less code duplication
- less burden on maintenance
- generalised qemu port, could in the future support other architectures
A new board `VIRT_RV32` has been added to the qemu-arm port which is the
existing RISC-V board from the qemu-riscv port. To build it:
$ make BOARD=VIRT_RV32 repl
To cleanly separate the code for the different architectures, startup code
has been moved to ports/qemu-arm/mcu/<arch>/.
Signed-off-by: Damien George <damien@micropython.org>
0426934969