cmake syntax fixes; fix variable name
cmake syntax fixes; fix variable name

autopulated/yotta,eyeye/yotta,BlackstoneEngineering/yotta,iriark01/yotta,stevenewey/yotta,ntoll/yotta,eyeye/yotta,autopulated/yotta,theotherjimmy/yotta,BlackstoneEngineering/yotta,ARMmbed/yotta,ARMmbed/yotta,theotherjimmy/yotta,bridadan/yotta,iriark01/yotta,stevenewey/yotta,bridadan/yotta,ntoll/yotta