samples: wifi: sta: Fix EK(SPI) build

STA sample can be used by DK's and EK's.

Signed-off-by: Chaitanya Tata <[email protected]>
(cherry picked from commit f94bd7b)

Author: krish2718

samples/wifi/sta/src/main.c

@@ -26,7 +26,10 @@ LOG_MODULE_REGISTER(sta, CONFIG_LOG_DEFAULT_LEVEL);
 #include <net/wifi_mgmt_ext.h>
 #include <net/wifi_ready.h>
 
+#if defined(CONFIG_BOARD_NRF7002DK_NRF7001_NRF5340_CPUAPP) || \
+	defined(CONFIG_BOARD_NRF7002DK_NRF5340_CPUAPP)
 #include <qspi_if.h>
+#endif
 
 #include "net_private.h"