According to the release notes, the Radeon Software 19.7.4 does not bring anything new other than a fix for Grand Theft Auto V application crash or hang issue seen on Radeon RX 5700 series graphics cards.
The release notes also mention a couple of known bugs, but nothing regarding higher idle fan speeds on the RX 5700 series.
In case you missed it, the earlier driver release, Radeon Software 19.7.3, raised idle fan speeds on RX 5700 series by over 50 percent. While this helped with idle temperatures, which dropped significantly on both the RX 5700 XT and the RX 5700, it raised the fan noise in idle state. Caught by Techpowerup.com, the release notes for Radeon Software 19.7.3, do not even talk about the new idle fan settings, nor these are fixed or listed as a problem in the latest Radeon Software 19.7.4 driver.
As always, the new Radeon Software 19.7.4 driver is available for 64-bit versions of Windows 7 and Windows 10 and support all graphics cards since Radeon HD 7700/HD 7900 days, as well as recent AMD APUs with Radeon and Vega graphics.
You can check out full release notes as well as find direct download links over at AMD's support page.