altera_jtaguart: Use dev_err() to report error attaching IRQ

In case of multiple Altera JTAG 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/20241029130307.5003-1-tklauser@distanz.ch


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