avcodec/svq1: Set hidden visibility

The encoder uses ff_svq1_inter_mean_vlc + 256 and setting
hidden visibility allows to bake this "+ 256" into the
general offset of ff_svq1_inter_mean_vlc and the code
accessing it.

For certain arches, this is also required for the compiler
to not produce overtly pessimistic code that can't be fixed
up by the linker lateron.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavcodec/svq1.h

@@ -37,6 +37,8 @@
 
 #include <stdint.h>
 
+#include "libavutil/attributes_internal.h"
+
 #define SVQ1_BLOCK_SKIP         0
 #define SVQ1_BLOCK_INTER        1
 #define SVQ1_BLOCK_INTER_4V     2
@@ -49,6 +51,7 @@
 #define SVQ1_BLOCK_INTRA_CODE   0
 #define SVQ1_BLOCK_INTRA_LEN    3
 
+FF_VISIBILITY_PUSH_HIDDEN
 extern const int8_t *const ff_svq1_inter_codebooks[6];
 extern const int8_t *const ff_svq1_intra_codebooks[6];
 
@@ -59,5 +62,6 @@ extern const uint16_t ff_svq1_intra_mean_vlc[256][2];
 extern const uint16_t ff_svq1_inter_mean_vlc[512][2];
 
 extern const uint16_t ff_svq1_frame_size_table[7][2];
+FF_VISIBILITY_POP_HIDDEN
 
 #endif /* AVCODEC_SVQ1_H */