wlcore: move wl12xx_platform_data up and make it truly optional

The platform data is used not only by wlcore-based drivers, but also
by wl1251.  Move it up in the directory hierarchy to reflect this.

Additionally, make it truly optional.  At the moment, disabling
platform data while wl1251_sdio or wlcore_sdio are enabled doesn't
work, but it will be necessary when device tree support is
implemented.

Signed-off-by: Luciano Coelho <coelho@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
diff --git a/include/linux/wl12xx.h b/include/linux/wl12xx.h
index 360c9bc..a54fe82 100644
--- a/include/linux/wl12xx.h
+++ b/include/linux/wl12xx.h
@@ -24,6 +24,8 @@
 #ifndef _LINUX_WL12XX_H
 #define _LINUX_WL12XX_H
 
+#include <linux/err.h>
+
 /* Reference clock values */
 enum {
 	WL12XX_REFCLOCK_19	= 0, /* 19.2 MHz */
@@ -60,10 +62,12 @@
 /* Platform does not support level trigger interrupts */
 #define WL12XX_PLATFORM_QUIRK_EDGE_IRQ	BIT(0)
 
-#ifdef CONFIG_WL12XX_PLATFORM_DATA
+#ifdef CONFIG_WILINK_PLATFORM_DATA
 
 int wl12xx_set_platform_data(const struct wl12xx_platform_data *data);
 
+struct wl12xx_platform_data *wl12xx_get_platform_data(void);
+
 #else
 
 static inline
@@ -72,8 +76,12 @@
 	return -ENOSYS;
 }
 
-#endif
+static inline
+struct wl12xx_platform_data *wl12xx_get_platform_data(void)
+{
+	return ERR_PTR(-ENODATA);
+}
 
-struct wl12xx_platform_data *wl12xx_get_platform_data(void);
+#endif
 
 #endif