This adds a new __freebsd_kprintf__ format string type, which enables
checking when used in __attribute__((format(...))) attributes. It can
check the FreeBSD kernel specific %b, %D, %r and %y specifiers, using
existing diagnostic messages. Also adds test cases for all these
specifiers.
Differential Revision: http://reviews.llvm.org/D7154
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229921 91177308-0d34-0410-b5e6-96231b3b80d8