altera_uart: Use dev_err() to report error attaching IRQ handler

In case of multiple Altera UART ports available on the system, the error
message will contain information about the port for which attaching the
IRQ handler failed.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241029130258.4679-1-tklauser@distanz.ch


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>