Sorry, failed to mention this is for an inherited IRA. I'm guessing IRS sees the whole total for 2016 RMD and 2017 RMD I took in 02/2017 as a 2017 distribution. Am I correct? If yes, then filling out form 5329 seems straight forward - lines 52-55 - and done.
you must fill out Form 5329 for 2016 to show what did (not) happen. There is a penalty tax imposed for this.
You may on the form request the IRS to waive part or all of that tax. attach a statement explaining your "reasonable cause" for missing that RMD.
Note: as of this writing Turbotax makes this difficult without a 1099-R to work with. you'd have to invent one, or prepare the form 5329 yourself.