Merge #13650: [travis] Don't store debug info if --enable-debug is set

14788fb [travis] Don't store debug info if --enable-debug is set (Chun Kuan Lee)

Pull request description:

  After #12686 merged, ccache store huge size of .o files, simply get rid of those useless debug info.

  Fixes #13748

Tree-SHA512: fb404e2c7d52cd8266548433955c41683ede062f97c8fb7098a887f164bcde48b60e5e533a0a27c7e095fdd9ef88db018b8689adebb2c0e32c8957828629e346

Author: MarcoFalke

.travis.yml

@@ -34,7 +34,7 @@ env:
 # 32-bit + dash
     - HOST=i686-pc-linux-gnu PACKAGES="g++-multilib python3-zmq" DEP_OPTS="NO_QT=1" RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --enable-glibc-back-compat --enable-reduce-exports LDFLAGS=-static-libstdc++" CONFIG_SHELL="/bin/dash"
 # x86_64 Linux (uses qt5 dev package instead of depends Qt to speed up build and avoid timeout)
-    - HOST=x86_64-unknown-linux-gnu PACKAGES="python3-zmq qtbase5-dev qttools5-dev-tools protobuf-compiler libdbus-1-dev libharfbuzz-dev libprotobuf-dev" DEP_OPTS="NO_QT=1 NO_UPNP=1 DEBUG=1 ALLOW_HOST_PACKAGES=1" RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --with-gui=qt5 --enable-glibc-back-compat --enable-reduce-exports --enable-debug"
+    - HOST=x86_64-unknown-linux-gnu PACKAGES="python3-zmq qtbase5-dev qttools5-dev-tools protobuf-compiler libdbus-1-dev libharfbuzz-dev libprotobuf-dev" DEP_OPTS="NO_QT=1 NO_UPNP=1 DEBUG=1 ALLOW_HOST_PACKAGES=1" RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --with-gui=qt5 --enable-glibc-back-compat --enable-reduce-exports --enable-debug CXXFLAGS=\"-g0 -O2\""
 # x86_64 Linux (Qt5 & system libs)
     - HOST=x86_64-unknown-linux-gnu PACKAGES="python3-zmq qtbase5-dev qttools5-dev-tools libssl1.0-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libzmq3-dev libprotobuf-dev protobuf-compiler libqrencode-dev" NO_DEPENDS=1 RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --with-incompatible-bdb --enable-glibc-back-compat --enable-reduce-exports --with-gui=qt5 CPPFLAGS=-DDEBUG_LOCKORDER"
 # x86_64 Linux, No wallet