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ARROW-12533: [C++] Add random real distribution function

Clang with gnu libstdc++ produces code very slow in generating random
real numbers on Arm64.

This patch implements three random utilities based on clang libc++:
- std::generate_canonical
- std::random_real_distribution
- std::bernoulli_distribution

It brings ~100x speedup on Arm64 and ~8x on x86_64 in generating
random reals when build arrow with clang + gnu libstdc++.
No influence to gcc + libstdc++, or clang + libc++.

Closes #10283 from cyb70289/12533-random-real

Authored-by: Yibo Cai <yibo.cai@arm.com>
Signed-off-by: Antoine Pitrou <antoine@python.org>