[Bug target/85719] New: Unclear docs for AVR io attribute

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85719

            Bug ID: 85719
           Summary: Unclear docs for AVR io attribute
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Keywords: documentation
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org
  Target Milestone: ---
            Target: avr-*-*

https://gcc.gnu.org/onlinedocs/gcc/AVR-Variable-Attributes.html#index-io-variable-attribute_002c-AVR
says

"The address specified in the address in the data address range."

What is this supposed to mean? Is it stating a requirement that users must
meet?

Also the grammar in the next paragraph should be fixed:

"Otherwise, the variable it is not assigned an address,"