check-cc-no-c-o: unify initializations in a single place * t/ax/test-defs.in: That is, by setting CC and GNU_CC here, in accord with the value of the variable 'AM_TESTSUITE_SIMULATING_NO_CC_C_O'. * t/Makefile.in (check-cc-no-c-o) : No need to reset CC and GNU_CC any longer in the recursive "make check" invocation. Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>