libgomp build: undeclared openacc stuff

[Tim Prince]

attempting to build from current trunk (configured with --disable-werror)
Shouldn't the openacc stuff in libgomp be disabled automatically (or by
some other means) for targets where it isn't supported?

../libgomp/oacc-init.c  -DDLL_EXPORT -DPIC -o .libs/oacc-init.o
../../../libgomp/oacc-init.c: In function ‘acc_on_device’:
../../../libgomp/oacc-init.c:587:3: error: implicit declaration of
function ‘__builtin_acc_on_device’ [-Werror=implicit-function-declaration]
   return __builtin_acc_on_device (dev);
   ^

-- 
Tim Prince