partition_search: Fix implicit declaration
Example warning:
```c
av1/encoder/partition_search.c: In function 'setup_block_rdmult':
av1/encoder/partition_search.c:432:5: warning: implicit declaration of function 'av1_set_vmaf_rdmult'; did you mean 'av1_set_ssim_rdmult'? [-Wimplicit-function-declaration]
432 | av1_set_vmaf_rdmult(cpi, x, bsize, mi_row, mi_col, &x->rdmult);
| ^~~~~~~~~~~~~~~~~~~
| av1_set_ssim_rdmult
```
Change-Id: I6dd2c888a983f63bb1e251da0d35dd25b4e957a4
diff --git a/av1/encoder/partition_search.c b/av1/encoder/partition_search.c
index 8a6ee65..1bcd142 100644
--- a/av1/encoder/partition_search.c
+++ b/av1/encoder/partition_search.c
@@ -28,6 +28,10 @@
#include "av1/encoder/tokenize.h"
#include "av1/encoder/var_based_part.h"
+#if CONFIG_TUNE_VMAF
+#include "av1/encoder/tune_vmaf.h"
+#endif
+
static void update_txfm_count(MACROBLOCK *x, MACROBLOCKD *xd,
FRAME_COUNTS *counts, TX_SIZE tx_size, int depth,
int blk_row, int blk_col,
