Remove unused avifReformatState.rgbChannelCount
diff --git a/include/avif/internal.h b/include/avif/internal.h
index 84974b0..31bf425 100644
--- a/include/avif/internal.h
+++ b/include/avif/internal.h
@@ -117,7 +117,6 @@
 
     uint32_t yuvChannelBytes;
     uint32_t rgbChannelBytes;
-    uint32_t rgbChannelCount;
     uint32_t rgbPixelBytes;
     uint32_t rgbOffsetBytesR;
     uint32_t rgbOffsetBytesG;
diff --git a/src/reformat.c b/src/reformat.c
index 951c46b..2200e8c 100644
--- a/src/reformat.c
+++ b/src/reformat.c
@@ -71,7 +71,6 @@
 
     state->yuvChannelBytes = (image->depth > 8) ? 2 : 1;
     state->rgbChannelBytes = (rgb->depth > 8) ? 2 : 1;
-    state->rgbChannelCount = avifRGBFormatChannelCount(rgb->format);
     state->rgbPixelBytes = avifRGBImagePixelSize(rgb);
 
     switch (rgb->format) {