coverity: Add custom assertion macros for Coverity
These custom macros make the expression go through a function, in order
to prevent ASSERT_SIDE_EFFECT false positives on our macros such as
assert_se() and assert_return() that cannot be disabled and will always
evaluate their expressions.
This technique has been described and recommended in:
https://community.synopsys.com/s/question/0D534000046Yuzb/suppressing-assertsideeffect-for-functions-that-allow-for-sideeffects
Tested by doing a local cov-build and uploading the resulting tarball to
scan.coverity.com, confirmed that the ASSERT_SIDE_EFFECT false positives
were gone.