intmath: remove av_ctz.

It's a non-installed header and only used in one place (flacenc).
Since ff_ctz is static inline, it's fine to use that instead.

doc/APIchanges

@@ -1052,9 +1052,6 @@ lavd 54.4.100 / 54.0.0, lavfi 3.5.0
 2012-11-11 - 03b0787 / 5980f5d - lavu 52.6.100 / 52.2.0 - audioconvert.h
   Rename audioconvert.h to channel_layout.h. audioconvert.h is now deprecated.
 
-2012-11-05 - 7d26be6 / dfde8a3 - lavu 52.5.100 / 52.1.0 - intmath.h
-  Add av_ctz() for trailing zero bit count
-
 2012-10-21 - e3a91c5 / a893655 - lavu 51.77.100 / 51.45.0 - error.h
   Add AVERROR_EXPERIMENTAL
 

libavcodec/flacenc.c

@@ -1065,7 +1065,7 @@ static void remove_wasted_bits(FlacEncodeContext *s)
         }
 
         if (v && !(v & 1)) {
-            v = av_ctz(v);
+            v = ff_ctz(v);
 
             for (i = 0; i < s->frame.blocksize; i++)
                 sub->samples[i] >>= v;

libavutil/intmath.c

@@ -32,8 +32,3 @@ int av_log2_16bit(unsigned v)
 {
     return ff_log2_16bit(v);
 }
-
-int av_ctz(int v)
-{
-    return ff_ctz(v);
-}

libavutil/intmath.h

@@ -122,6 +122,12 @@ static av_always_inline av_const int ff_log2_16bit_c(unsigned int v)
 
 #ifndef ff_ctz
 #define ff_ctz ff_ctz_c
+/**
+ * Trailing zero bit count.
+ *
+ * @param v  input value. If v is 0, the result is undefined.
+ * @return   the number of trailing 0-bits
+ */
 #if !defined( _MSC_VER )
 static av_always_inline av_const int ff_ctz_c(int v)
 {
@@ -177,14 +183,6 @@ static av_always_inline av_const int ff_ctzll_c(long long v)
 }
 #endif
 
-/**
- * Trailing zero bit count.
- *
- * @param v  input value. If v is 0, the result is undefined.
- * @return   the number of trailing 0-bits
- */
-int av_ctz(int v);
-
 /**
  * @}
  */