msdos cross-compile djggp build now with gcc 10

Also updates the travis build to Ubuntu focal because of an
ar libfl.so.2 shared library load error on xenial that was
easier to just get away from by moving to focal.

.travis.yml

@@ -135,12 +135,15 @@ matrix:
         - cd src
         - cp ../sys/winnt/Makefile.gcc ./Makefile
         - mingw32-make install
-    - name: msdos-linuxhost-crosscompile
+    - name: msdos-linux-focal-djgpp-crosscompile
       os: linux
       env: HINTS=linux LUA_VERSION=5.4.0
+      dist: focal
       compiler: gcc
       script:
 #        - export
+#        - export GCCVER=gcc550
+        - export GCCVER=gcc1010
         - cd sys/unix/ && sh setup.sh hints/$HINTS && cd ../../
         - make fetch-lua
         - test -d "lib/lua-$LUA_VERSION/src" || exit 0

sys/msdos/msdos-cross-compile.sh

@@ -12,16 +12,17 @@ if [ ! -d "$(pwd)/lib" ]; then
 	exit 1
 fi
 
-DJGPP_URL="https://github.com/andrewwutw/build-djgpp/releases/download/v2.9/"
+#DJGPP_URL="https://github.com/andrewwutw/build-djgpp/releases/download/v2.9/"
+DJGPP_URL="https://github.com/andrewwutw/build-djgpp/releases/download/v3.0/"
 if [ "$(uname)" = "Darwin" ]; then
     #Mac
-    DJGPP_FILE="djgpp-osx-gcc550.tar.bz2"
+    DJGPP_FILE="djgpp-osx-$GCCVER.tar.bz2"
 elif [ "$(expr substr $(uname -s) 1 5)" = "Linux" ]; then
     #Linux
-    DJGPP_FILE="djgpp-linux64-gcc550.tar.bz2"
+    DJGPP_FILE="djgpp-linux64-$GCCVER.tar.bz2"
 elif [ "$(expr substr $(uname -s) 1 10)" = "MINGW32_NT" ]; then
     #mingw
-    DJGPP_FILE="djgpp-mingw-gcc550-standalone.zip"
+    DJGPP_FILE="djgpp-mingw-$GCCVER-standalone.zip"
 else
     echo "No DJGPP release for you, sorry."
     exit 1