mt76: mt7915: fix endianness in mt7915_rf_regval_get

Fix the following sparse warning in mt7915_rf_regval_get routine:
drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c:979:16: warning: cast to restricted __le32

Fixes: 0a17329a ("mt76: mt7915: add debugfs knob for RF registers read/write")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c

@@ -976,7 +976,7 @@ mt7915_rf_regval_get(void *data, u64 *val)
 	if (ret)
 		return ret;
 
-	*val = le32_to_cpu(regval);
+	*val = regval;
 
 	return 0;
 }