ttyd: Fix build without requiring xxd

packages/ttyd/build.sh

@@ -4,4 +4,12 @@ TERMUX_PKG_VERSION=1.4.2
 TERMUX_PKG_SHA256=ff1a66b418df6cd741868a8ea84f69cd63f15e52e3fa117641ec57d3c37a1315
 TERMUX_PKG_SRCURL=https://github.com/tsl0922/ttyd/archive/$TERMUX_PKG_VERSION.tar.gz
 TERMUX_PKG_DEPENDS="json-c, libwebsockets, libutil"
-TERMUX_PKG_EXTRA_CONFIGURE_ARGS="-DCMAKE_XXD=`which xxd`"
+TERMUX_PKG_EXTRA_CONFIGURE_ARGS="-DCMAKE_XXD=$TERMUX_PKG_TMPDIR/xxd"
+
+termux_step_pre_configure() {
+	termux_download \
+		https://raw.githubusercontent.com/vim/vim/v8.1.0427/src/xxd/xxd.c \
+		$TERMUX_PKG_CACHEDIR/xxd.c \
+		021b38e02cd31951a80ef5185271d71f2def727eb8ff65b7a07aecfbd688b8e1
+	gcc $TERMUX_PKG_CACHEDIR/xxd.c -o $TERMUX_PKG_TMPDIR/xxd
+}