lib: earlycpio: export symbol find_cpio_data()

Add EXPORT_SYMBOL_GPL() for find_cpio_data() so that loadable modules
may also parse uncompressed cpio.

Signed-off-by: Richard Oliver <richard.oliver@raspberrypi.com>

lib/earlycpio.c

@@ -139,3 +139,4 @@ struct cpio_data find_cpio_data(const char *path, void *data,
 quit:
 	return cd;
 }
+EXPORT_SYMBOL_GPL(find_cpio_data);