CP2102 device is not listed in /dev on macOS 10.13
I found that macOS High Sierra has blocked all unsigned / unmanaged kernel extensions and the SiLabs kernel extension guide doesn’t have information on how to manually enable the required extensions.

An excellent overview of this process is at man blogs - here is one such guide:


https://grahamgilbert.com/blog/2017/09/11/enabling-kernel-extensions-in-high-sierra/ 


Here are steps to allow this extension specifically:


Go to "System Preferences" -> "Security &amp; Privacy" 
In the bottom of the window, you will see a message "System software from developer "SiLabs" was blocked from loading." 
Click on "Allow" button
Restart your Mac


Now my device is listed as /dev/cu.SLAB_USBtoUART and everything work as expected.