ASoC: Intel: avs: Include missing string.h

File loader.c utilizes strscpy().

Reviewed-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://patch.msgid.link/20250530141025.2942936-10-cezary.rojewski@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: crojewsk-intel

sound/soc/intel/avs/loader.c

@@ -9,6 +9,7 @@
 #include <linux/firmware.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/string.h>
 #include <sound/hdaudio.h>
 #include <sound/hdaudio_ext.h>
 #include "avs.h"