avcodec/hevc_ps: fix storage type for some PPS multilayer extension fields

The spec states that the range of values for them is −2^14 to 2^14 − 1, inclusive.

Signed-off-by: James Almer <jamrial@gmail.com>

libavcodec/hevc_ps.h

@@ -317,15 +317,15 @@ typedef struct HEVCPPS {
     uint8_t num_ref_loc_offsets;
     uint8_t ref_loc_offset_layer_id[64];
     uint8_t scaled_ref_layer_offset_present_flag[64];
-    int8_t scaled_ref_layer_left_offset[64];
-    int8_t scaled_ref_layer_top_offset[64];
-    int8_t scaled_ref_layer_right_offset[64];
-    int8_t scaled_ref_layer_bottom_offset[64];
+    int16_t scaled_ref_layer_left_offset[64];
+    int16_t scaled_ref_layer_top_offset[64];
+    int16_t scaled_ref_layer_right_offset[64];
+    int16_t scaled_ref_layer_bottom_offset[64];
     uint8_t ref_region_offset_present_flag[64];
-    int8_t ref_region_left_offset[64];
-    int8_t ref_region_top_offset[64];
-    int8_t ref_region_right_offset[64];
-    int8_t ref_region_bottom_offset[64];
+    int16_t ref_region_left_offset[64];
+    int16_t ref_region_top_offset[64];
+    int16_t ref_region_right_offset[64];
+    int16_t ref_region_bottom_offset[64];
     uint8_t resample_phase_set_present_flag[64];
     uint16_t phase_hor_luma[64];
     uint16_t phase_ver_luma[64];