Under ./configure --without-numactl but with numactl-devel installed,
the build fails with:

../../src/util/virnuma.c: In function 'virNumaNodeIsAvailable':
../../src/util/virnuma.c:407:5: error: implicit declaration of function 'numa_bitmask_isbitset' [-Werror=implicit-function-declaration]
     return numa_bitmask_isbitset(numa_nodes_ptr, node);
     ^

and other failures, all because the configure results for particular
functions were used without regard to whether libnuma was even being
linked in.

* src/util/virnuma.c (virNumaGetPages): Fix message typo.
(virNumaNodeIsAvailable): Correct build when not using numactl.
Signed-off-by: NEric Blake <eblake@redhat.com>