Fix libpng not found

Author: Khang-NT

build_scripts/build_ffmpeg.sh

@@ -322,6 +322,21 @@ if [ "$FLAVOR" = "full" ]; then
         make install
     popd
 
+    pushd libpng-${LIBPNG_VERSION}
+        ./configure \
+            --prefix=$PREFIX \
+            --host=$HOST \
+            --with-pic \
+            --enable-static \
+            --disable-shared \
+            --enable-arm-neon="$ARM_NEON" \
+            --disable-shared
+
+        make clean 
+        make -j8
+        make install
+    popd
+
     pushd freetype-${LIBFREETYPE_VERSION}
         ./configure \
             --prefix=$PREFIX \
@@ -364,21 +379,6 @@ if [ "$FLAVOR" = "full" ]; then
         make install
     popd
 
-    pushd libpng-${LIBPNG_VERSION}
-        ./configure \
-            --prefix=$PREFIX \
-            --host=$HOST \
-            --with-pic \
-            --enable-static \
-            --disable-shared \
-            --enable-arm-neon="$ARM_NEON" \
-            --disable-shared
-
-        make clean 
-        make -j8
-        make install
-    popd
-
     pushd fontconfig-${LIBFONTCONFIG_VERSION}
         autoreconf -iv
         ./configure \