avcodec/loongarch/cabac, vp9dsp_loongarch: Add missing headers

Fixes checkheaders on loongarch.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavcodec/loongarch/cabac.h

@@ -25,6 +25,7 @@
 #ifndef AVCODEC_LOONGARCH_CABAC_H
 #define AVCODEC_LOONGARCH_CABAC_H
 
+#include "libavutil/attributes.h"
 #include "libavcodec/cabac.h"
 #include "config.h"
 

libavcodec/loongarch/vp9dsp_loongarch.h

@@ -22,6 +22,9 @@
 #ifndef AVCODEC_LOONGARCH_VP9DSP_LOONGARCH_H
 #define AVCODEC_LOONGARCH_VP9DSP_LOONGARCH_H
 
+#include <stddef.h>
+#include <stdint.h>
+
 #define VP9_8TAP_LOONGARCH_LSX_FUNC(SIZE, type, type_idx)                    \
 void ff_put_8tap_##type##_##SIZE##h_lsx(uint8_t *dst, ptrdiff_t dststride,   \
                                         const uint8_t *src,                  \