[Bug target/60808] New: Typo in definition of ATxmega256A3BU

[vonzeng at ibr dot cs.tu-bs.de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60808

            Bug ID: 60808
           Summary: Typo in definition of ATxmega256A3BU
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: vonzeng at ibr dot cs.tu-bs.de

Created attachment 32579
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32579&action=edit
typo fix

There is a typo in gcc/config/avr/avr-mcus.de. 
The mmcpu definition of the ATxmega256A3BU is __AVR_ATxmega258A3BU__.
This leads to errors while compiling the avr-libc, this is way I marked the bug
critical.
Attached is the very easy patch to fix it.