xbps-src [chroot]: try different shells for /bin/sh symlinks.

xbps-src/shutils/chroot.sh.in

@@ -183,7 +183,17 @@ _EOF
 create_binsh_symlink()
 {
 	if [ ! -h $XBPS_MASTERDIR/bin/sh ]; then
-		cd $XBPS_MASTERDIR/bin && ln -sf bash sh
+		cd $XBPS_MASTERDIR/bin
+		if [ -x bash ]; then
+			ln -sf bash sh
+		elif [ -x dash ]; then
+			ln -sf dash sh
+		elif [ -x busybox ]; then
+			ln -sf busybox sh
+		else
+			msg_error "cannot find a suitable shell for chroot!\n"
+		fi
+
 	fi
 }