avcodec/aacdec_templat: Fix integer overflow in apply_ltp()

Fixes: signed integer overflow: -1625276744 + -1041893960 cannot be represented in type 'int'
Fixes: 5948/clusterfuzz-testcase-minimized-5791479856365568

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/aacdec_template.c

@@ -2561,7 +2561,7 @@ static void apply_ltp(AACContext *ac, SingleChannelElement *sce)
         for (sfb = 0; sfb < FFMIN(sce->ics.max_sfb, MAX_LTP_LONG_SFB); sfb++)
             if (ltp->used[sfb])
                 for (i = offsets[sfb]; i < offsets[sfb + 1]; i++)
-                    sce->coeffs[i] += predFreq[i];
+                    sce->coeffs[i] += (UINTFLOAT)predFreq[i];
     }
 }