RISC-V: Implement backend for 'write_debug' host function
What
Implements the backend for the write_debug
host function.
Why
Kernels would like to write debug output.
How
Adds a runtime configuration component to the execution environment trait. This configuration object is used in PvmSbiState
's implementation of the SBI_LEGACY_PUTCHAR
handler to funnel characters outside of the PVM.
Manually testing the MR
cargo test test_write_debug
Edited by Ole Krüger