debug: fix HwbpManual test

HwbpManual test was broken:
* Value read back from `tselect` was compared with `tdata1` value.
https://github.com/riscv-software-src/riscv-tests/blob/408e461da11e0b298c4b69e587729532787212f5/debug/gdbserver.py#L701-L703
This resulted in the test being reported as not supported, after all the
triggers were checked.
* `tdata1.type` field was not set to `mcontrol`.
* `tselect` value used to be changed by `handle_reset` and not restored.
https://github.com/riscv-software-src/riscv-tests/blob/408e461da11e0b298c4b69e587729532787212f5/debug/programs/entry.S#L79-L84


* Manual breakpoint used to be left behind.

Signed-off-by: Evgeniy Naydanov <evgeniy.naydanov@syntacore.com>