[analyzer] Command line option to show enabled checker list.
This patch adds a command line option to list the checkers that were enabled
by analyzer-checker and not disabled by -analyzer-disable-checker.
It can be very useful to debug long command lines when it is not immediately
apparent which checkers are turned on and which checkers are turned off.
Differential Revision: https://reviews.llvm.org/D23060
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278006
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