Log Message:
Upgrade avr-libc to version 1.2.5.

avr-libc-1.2.5 is the 5th bugfix release after 1.2.
The following list shortly summarizes the changes in version 1.2.0 compared
to version 1.0.5 of AVR Libc, which was the latest release from the 1.0
release line by the time 1.2.0 was released.

    * Removal of all items marked as deprecated in the past, namely:
          o all header files from the base include directory, as they have
            been moved to the avr/ subdirectory long time ago (e.g. <io.h>
            is now <avr/io.h>),
          o deprecated macros and functions (sbi, cbi, inb, outb, inp, outp,
            inw, outw, BV, PRG_RDB, eeprom_rb, eeprom_rw, eeprom_wb)
          o <avr/timer.h> removed completely, as it was bogus and not really
            useful at all
    * <avr/ina90.h> and <avr/twi.h> have been moved to the new \ 
<compat/...>
      include subdirectory,
    * The following new devices are supported:
          o ATmega165
          o ATmega325
          o ATmega3250
          o ATmega645
          o ATmega6450
          o ATmega48
          o ATmega88
          o ATmega168
          o ATtiny13
          o ATtiny2313
          o AT90CAN128
    * realloc() is now implemented,
    * the boot API has been changed in a way that is incompatible with the
      1.0 API,
    * the delay API has two new functions added to allow the specification of
      delays directly in microseconds, or milliseconds,
    * documentation changes: a newer version of Doxygen is used; Unix-style
      manual pages are now generated as part of the documentation; a helper
      script named avr-man can be used to display these manual pages,
    * a single unified Copyright now applies to all files in AVR Libc.