patman: Add a 'test' subcommand

At present we use --test to indicate that tests should be run. It is
better to use a subcommand for list, like binman. Change it and adjust
the existing code to fit under a 'send' subcommand, the default.

Give this subcommand the same default arguments as the others.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/.azure-pipelines.yml b/.azure-pipelines.yml
index 303857c..9ba9f1d 100644
--- a/.azure-pipelines.yml
+++ b/.azure-pipelines.yml
@@ -158,7 +158,7 @@
           ./tools/binman/binman --toolpath ${UBOOT_TRAVIS_BUILD_DIR}/tools test
           ./tools/buildman/buildman -t
           ./tools/dtoc/dtoc -t
-          ./tools/patman/patman --test
+          ./tools/patman/patman test
           make O=${UBOOT_TRAVIS_BUILD_DIR} testconfig
           EOF
           cat build.sh