By itself that isn't circular reasoning, it is an appeal to authority.

It is when you are then asked why you trust what rishis and yogis say that things start to bend in on themselves into a circular argument.

A Western (specifically, Judeo-Christian) example:

"I believe X, because the Bible says so."

"How do you know that what the Bible says is true?"

"Because the Bible is the inerrant word of God."

"And how do you know that?"

"The Bible says so."

"And how do you know that what the Bible says is true?"

... etc.

By itself, the first statement is only an appeal to authority, but when you dig into the source of the authority, it (rather quickly) turns into a circular argument.