Fix a couple typos on the incarch i-command name for error and help
messages.

Just a couple minor bugs noticed while updating documentation.  Looks
like the i-command name wasn't updated when the base code, incattr.c,
was used to make incarch.c.



git-svn-id: svn://irodssvn.ucsd.edu/trunk@5681 ea137bd6-aa86-47b6-b90d-b101d9f19a90