serial: serial-tegra: reduce irq-latency after rx errors

serial: serial-tegra: reduce irq-latency after rx errors

Since dev_err() calls can lead to synchronous writes to another serial
console these calls can provide significant latency during irq-handling
in tegra_uart_isr(). With this latency another interrupt is likely to
apper during handling of the first interrupt, which might lock up the
kernel completely.

These errors are reported to the error counters so converting the
dev_err() to dev_dbg() is appropriate.

Signed-off-by: Randolph Maaßen <gaireg@gaireg.de>
Link: https://lore.kernel.org/r/20200605145714.9964-1-gaireg@gaireg.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>