They look like wallows to me!
The easiest way to tell if it's a pig or deer that has been in a wallow is to look at the tracks, generally pig tracks are very round while deer are more oblong/oval. The toes on pig tracks are also very sharp and can look like they have claws (i.e. look like two-toed dog tracks). Pigs will generally rub on a nearby punga or other tree after wallowing, so look for fresh mud on tree trunks. Also look for hair in the wallow.