MariaDB is violating clang-16 -Wcast-function-type-strict

D134831 introduced a compile-time check -Wcast-function-type-strict for something that had been reported by -fsanitize=undefined for a long time.

The flag is similar to the non-strict GCC check that we have for a long time enabled by -Wextra.

We should fix all occurrences of this warning and enable this warning in our build script when available, so that the mandatory MemorySanitizer builder that is based on clang-16 or later would fail already at compilation time.