hdf5_msb

[svn-r23260] Bug fix: HDFFV-8267
The ERROR macro had a typo of missing a separator comma. When used, it seg.
fault. Added the comma back in.
Fix is reviewed in Crucible HDF5-107.

Tested: h5committest passed. Also tested using the ERROR macro in the
Mac (Owl) platform. Before fix, it seg. fault. After fix, it prints the
message as intended.