vmem: do not reinitialize the dss_mtx mutex

The dss_mtx mutex is locked at chunk_dss.c:50
(called from malloc_init_base_pool() at jemalloc.c:362)
before being initialized at chunk_dss.c:167
(called from malloc_init_base_pool() at jemalloc.c:364).

Move call to chunk_dss_boot() to chunk_global_boot()
in order to fix this bug.

Ref: pmem/issues#16
benchmarks/blk_mt: fix error messages

Ref: pmem/issues#11
common: fix all *_check_version() functions

Ref: pmem/issues#10
Merge pull request #64 from ldorau/benchmarks-blk_mt-fix-error-messages

benchmarks/blk_mt: fix error messages
Merge pull request #66 from ldorau/vmem-do-not-reinitialize-the-dss_mtx-mutex

vmem: do not reinitialize the dss_mtx mutex
Merge pull request #65 from ldorau/vmem-fix-vmem_check_version

common: fix all *_check_version() functions