ref. #1262

Replaced with code by yours truly, © Intel.

disable 'maybe-uninitialized' compiler flag

in tests, examples and benchmarks - it produces many false-positives.

tests: add drd/memcheck suppressions

Taken from https://github.com/pmem/pmdk/commit/02762f3eba6f3f69f81343925c82db6b0200a426

inline_string: add missing specialization for total_sizeof

inline_string: implement copy assignment operator

Older compilers have problems with using assignment operator
from the base class.

[inline_string] Differentiate inline_string on PMEM and DRAM

instead of basic_inline_string so that there is no implicit
copy of inline_string when string_view is passed.

Authored by: Igor Chorazewicz