"The suit's pockets are small."
Translation:Les poches du costume sont petites.
"The suit pockets are small": suit is a noun acting as an adjective qualifying which are the pockets we are talking about. No genitive apostrophe S (’s) is required here.
"The Rules: We normally use the ’s with people, animals though it can also be used with places, organizations and companies (which suggest a group of people). It is not common to use the ’s with non-living things." http://www.grammar.cl/rules/genitive-case.htm