Since C++20 classes with explicitly defaulted constructors are no more
aggregates, so constructor for initialization_list is needed.

Fix CI scripts

riscv: define cacheline size

More radix fixes

[ebr+tagged_ptr] add assignment declarations needed by Klocwork.

If the tree contains only a single element smaller than the
looked-for key, radix_tree tried to call make_iterator on nullptr.

This resulted in segfaults in pmemkv tests.

Bug found with the help of UBSAN.

Klocwork said: "Class 'atomic/worker' defines a copy constructor,
but no assignment operator".

Small fixes for coverity issues

Mpsc queue docs

Merge stable-1.12 into master

Mpsc queue remove overload with copying data in lambda function

Merge stable-1.11 into stable-1.12

It seems it is unecessary compicated to use.

Merge stable-1.10 into stable-1.11

Merge stable-1.9 into stable-1.10

Fix mpsc queue const

CI: remove Travis CI configuration on stable branches

Set secret github token, for auto doc update.

Merge stable-1.8 into stable-1.9

tests: link atomic to all tests

Not only self_relative_ptr tests use atomics. On some platforms
(e.g. riscv64) -latomic is needed for a few other tests
(pool_cleanup, volatile_state).

Merge stable-1.7 into stable-1.8