[committed] restrict gcc.target/m68k/pr36134.c to ColdFire

[Sandra Loosemore]

I've checked in this patch, which was conditionally approved 3+ years ago:
http://gcc.gnu.org/ml/gcc-patches/2009-05/msg00688.html

I did look at general usage for m68k and adding -mcpu is consistent with 
other existing tests; there aren't enough of them that are 
conditionalized in this way to justify adding a more complicated test 
framework.

-Sandra