tty: sunsu: remove unused serial_icr_read()

It is commented and never used.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Link: https://lore.kernel.org/r/20250317070046.24386-25-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Jiri Slaby (SUSE)

drivers/tty/serial/sunsu.c

@@ -159,20 +159,6 @@ static void serial_icr_write(struct uart_sunsu_port *up, int offset, int value)
 	serial_out(up, UART_ICR, value);
 }
 
-#if 0 /* Unused currently */
-static unsigned int serial_icr_read(struct uart_sunsu_port *up, int offset)
-{
-	unsigned int value;
-
-	serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
-	serial_out(up, UART_SCR, offset);
-	value = serial_in(up, UART_ICR);
-	serial_icr_write(up, UART_ACR, up->acr);
-
-	return value;
-}
-#endif
-
 #ifdef CONFIG_SERIAL_8250_RSA
 /*
  * Attempts to turn on the RSA FIFO.  Returns zero on failure.