The rdma-core driver.h include is no longer installed:
56dd87acd2
So ibv_read_sysfs_file() is not defined. As the symbols is still
distributed, we simply add the missing prototype manually.
Similarly, the gaspi_get_system_mem() function is not available from the
gaspi public headers, so we define it in the max_mem.c test.
Fixes: rarias/bscpkgs#7
Reviewed-by: Aleix Boné <abonerib@bsc.es>
Tested-by: Rodrigo Arias Mallo <rodrigo.arias@bsc.es>
