sound: oss: Use kernel_read_file_from_path() for mod_firmware_load()

Since recently we have kernel_read_file_from_path(), and it's doing
the same thing as our own home-baked mod_firmware_load().  Let's use
the official API function and clean up the old code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/oss/sound_firmware.h b/sound/oss/sound_firmware.h
index 0a0cbfd..da4c67e 100644
--- a/sound/oss/sound_firmware.h
+++ b/sound/oss/sound_firmware.h
@@ -1,2 +1,29 @@
-extern int mod_firmware_load(const char *fn, char **fp);
+#include <linux/fs.h>
 
+/**
+ *	mod_firmware_load - load sound driver firmware
+ *	@fn: filename
+ *	@fp: return for the buffer.
+ *
+ *	Load the firmware for a sound module (up to 128K) into a buffer.
+ *	The buffer is returned in *fp. It is allocated with vmalloc so is
+ *	virtually linear and not DMAable. The caller should free it with
+ *	vfree when finished.
+ *
+ *	The length of the buffer is returned on a successful load, the
+ *	value zero on a failure.
+ *
+ *	Caution: This API is not recommended. Firmware should be loaded via
+ *	request_firmware.
+ */
+static inline int mod_firmware_load(const char *fn, char **fp)
+{
+	loff_t size;
+	int err;
+
+	err = kernel_read_file_from_path((char *)fn, (void **)fp, &size,
+					 131072, READING_FIRMWARE);
+	if (err < 0)
+		return 0;
+	return size;
+}