rbd: fix 32-bit build
rbd: fix 32-bit build

%zu is not always synonymous with uint64_t; on 32-bit machines,
size_t is only 32 bits.  Prefer "%lld"/'unsigned long long' when
the variable is under our control, and "%"PRIu64 when we are
stuck with 'uint64_t' from RBD.

Fixes errors such as:

../../src/storage/storage_backend_rbd.c: In function 'virStorageBackendRBDVolWipe':
../../src/storage/storage_backend_rbd.c:1281:15: error: format '%zu' expects argument of type 'size_t', but argument 8 has type 'uint64_t {aka long long unsigned int}' [-Werror=format=]
     VIR_DEBUG("Need to wipe %zu bytes from RBD image %s/%s",
               ^
../../src/util/virlog.h:90:73: note: in definition of macro 'VIR_DEBUG_INT'
     virLogMessage(src, VIR_LOG_DEBUG, filename, linenr, funcname, NULL, __VA_ARGS__)
                                                                         ^
../../src/storage/storage_backend_rbd.c:1281:5: note: in expansion of macro 'VIR_DEBUG'
     VIR_DEBUG("Need to wipe %zu bytes from RBD image %s/%s",
     ^

Signed-off-by: Eric Blake <a9da18479c871fe903d9590822cfe2629c6a4d11@redhat.com>

nertpinx/libvirt,eskultety/libvirt,taget/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,VenkatDatta/libvirt,olafhering/libvirt,crobinso/libvirt,zippy2/libvirt,libvirt/libvirt,jfehlig/libvirt,nertpinx/libvirt,datto/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,nertpinx/libvirt,andreabolognani/libvirt,libvirt/libvirt,jardasgit/libvirt,olafhering/libvirt,jfehlig/libvirt,jfehlig/libvirt,eskultety/libvirt,zippy2/libvirt,andreabolognani/libvirt,jfehlig/libvirt,crobinso/libvirt,nertpinx/libvirt,datto/libvirt,crobinso/libvirt,VenkatDatta/libvirt,taget/libvirt,fabianfreyer/libvirt,eskultety/libvirt,olafhering/libvirt,taget/libvirt,datto/libvirt,eskultety/libvirt,VenkatDatta/libvirt,libvirt/libvirt,olafhering/libvirt,fabianfreyer/libvirt,eskultety/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,datto/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,jardasgit/libvirt,andreabolognani/libvirt,taget/libvirt,zippy2/libvirt,taget/libvirt,crobinso/libvirt,zippy2/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,libvirt/libvirt,fabianfreyer/libvirt,datto/libvirt