In other Netbeans version (e.g., Java), Comments category is available in this menu:
Disabling comments formatting can be done in this menu in Netbeans Java but not in Netbeans PHP.
I believe it's been several versions already but this functionality is still missing in the Netbeans PHP version.
Is there a way to manually disable comments formatting somewhere in the Netbeans config file? Note: This is Netbeans 8.2
I don't think there is a solution for this in the short term.
I'm not sure if it is exactly what you want, but there is a planned fix for NetBeans Bug 230814 "Auto creation of * in comments should only apply to /** blocks and not to /* blocks":
Netbeans doesn't currently allow you to do simple multiline comments in php without breaking the formatting. Multi line comments should be a trivial feature of any simple text editor or basic IDE, let alone a mature one like Netbeans.
Unfortunately the fix will not be applied until "after NetBeans 9.0 is released", which should be happening within the next few weeks.
You can download a beta release of NetBeans 9.0 as a zip file, but that probably won't help you unless they decided to include the fix as part of the 9.0 release after all.