package/libabseil-cpp new package

This package is a new dependency on grpc versions > 1.25.0

Tested with the following distributions:
  - Debian 9
  - CentOS 7
  - Fedora 32

Signed-off-by: Adam Duskett <Aduskett@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>