runastyle

[ci skip]
ValueFlow: extend aftercondition analysis below conditional code
ValueFlow: better analysis in valueFlowAfterCondition of 'if|while ( %var% )' etc
avr.cfg: Added more defines.
avr.cfg: Cleanup.
Made static local variable non-static (thread-safety, #5934)
Fixed #error handling:
- Reporting them once is enough
- Don't report them if --force is used - since we silently drop these configurations when we check multiple configurations. Without the fix, -f combined with -D resulted in #error being shown erroneously.
- No redundant preprocessor instance to report them
Fixed test_matchcompiler.py
travis: replace kernel check with clang check.

Check clang instead of kernel, which is a lot faster.
Make clang check failure fatal to the build.
travis: run test_matchcompiler.py
travis: move CHECK_INTERNAL check up, remove "SRCDIR=build VERIFY=1" job in favor of "MAKEFLAGS="HAVE_RULES=yes" SRCDIR=build VERIFY=1"
travis: add -DCHECK_INTERNAL to the VERIFY=1 job to automatically fetch issues like #5869 via travis
travis: run cppcheck with --exception-handling where it matters, update clang repo hash, check clang with enable=all, inconclusive.