Since we use different preprocessing bioconductor packages for the array chips with only PM probes design and the ones having both PM and MM probes based design. My precise question is how do we determine that which of the affy chips have the PM only design and which of them have both PM and MM design?

Thanks in advance 

As a general rule, all of the 3'-biased arrays are PM/MM, and everything after that has been PM-only (there are at least a couple of exceptions to that, however). The 3'-biased arrays (at least most of them) have cdf packages available at Bioconductor (go here and search the table for cdf).

There are more exacting ways to tell, but that would require you to do more than using a general rule. Like, for example, going to the ThermoFisher website and trying to find the documentation or the supporting information. You could hypothetically use the AffyCompatible package to query for cdf or clf/pgf/mps files for each array (where the existence of a cdf is a pretty good indication that the array is PM/MM, but again, not 100%).

That said, there is no compelling reason to process the PM/MM arrays any differently than the PM-only arrays. The RMA algorithm is the de facto standard for Affy array processing, and while you may get moderately different results using something else (like gcrma) for the PM/MM arrays, it's not clear that in general usage the extra work will change your results materially.