pool: fix removing pool with remote replica

src/libpmempool/libpmempool.c

src/libpmempool/rm.c

src/test/Makefile

src/test/libpmempool_rm/Makefile.inc

src/test/libpmempool_rm_remote/Makefile

src/test/libpmempool_rm_remote/TEST0

src/test/libpmempool_rm_remote/TEST1

src/test/libpmempool_rm_remote/TEST2

src/test/libpmempool_rm_remote/TEST3

src/test/libpmempool_rm_remote/config.sh

src/test/unittest/unittest.sh