hw/char/pl011: Improve RX flow tracing events

Log FIFO use (availability and depth).

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luc Michel <luc.michel@amd.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250220092903.3726-4-philmd@linaro.org>
2 files changed