net: dsa: qca8k: add CONFIG_LEDS_TRIGGERS dependency

Without LED triggers, the driver now fails to build:

drivers/net/dsa/qca/qca8k-leds.c: In function 'qca8k_parse_port_leds':
drivers/net/dsa/qca/qca8k-leds.c:403:31: error: 'struct led_classdev' has no member named 'hw_control_is_supported'
  403 |                 port_led->cdev.hw_control_is_supported = qca8k_cled_hw_control_is_supported;
      |                               ^

There is a mix of 'depends on' and 'select' for LEDS_TRIGGERS, so it's
not clear what we should use here, but in general using 'depends on'
causes fewer problems, so use that.

Fixes: e0256648 ("net: dsa: qca8k: implement hw_control ops")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/qca/Kconfig

@@ -20,6 +20,7 @@ config NET_DSA_QCA8K_LEDS_SUPPORT
 	bool "Qualcomm Atheros QCA8K Ethernet switch family LEDs support"
 	depends on NET_DSA_QCA8K
 	depends on LEDS_CLASS=y || LEDS_CLASS=NET_DSA_QCA8K
+	depends on LEDS_TRIGGERS
 	help
 	  This enabled support for LEDs present on the Qualcomm Atheros
 	  QCA8K Ethernet switch chips.