bug#24416: address@hidden is broken

[Thompson, David]

avr-gcc cannot find device-specific libraries when compiling, which
from my reading is due to a problem with multilib.  However, address@hidden
works fine!

avr-gcc -O2 -DF_CPU=16000000UL -mmcu=atmega32u4 test.c -o test
avr-ld: cannot find -lm
avr-ld: cannot find -lc
avr-ld: cannot find -latmega32u4
collect2: error: ld returned 1 exit status

The libraries in question here are located within
/gnu/store/...-avr-libc-2.0.0/avr/lib/avr5 but avr-gcc is only
searching within /avr/lib.

For now, I'm just using address@hidden and moving on with life.

- Dave