samples: driver: led_apa102c: change hard-coded device name

Use the config name defined by the driver Kconfig in device
binding calls as that is safer because device name can change and
the app does not need to change.

Jira: ZEP-1764

Change-Id: I5a3e16e10f7700ec12edbd07603808cd32f15755
Signed-off-by: Kuo-Lang Tseng <[email protected]>

Author: kltseng

samples/drivers/led_apa102c/src/main.c

@@ -35,7 +35,7 @@
 #define GPIO_CLK_PIN	19
 #define GPIO_NAME	"GPIO_"
 
-#define GPIO_DRV_NAME	"GPIO_0"
+#define GPIO_DRV_NAME	CONFIG_GPIO_QMSI_0_NAME
 
 #define APA102C_START_FRAME	0x00000000
 #define APA102C_END_FRAME	0xFFFFFFFF