fix: remove source locator for IO in FixedIOModule (#4500)

Signed-off-by: unlsycn <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: unlsycn

src/main/scala/chisel3/FixedIOModule.scala

@@ -3,7 +3,7 @@
 package chisel3
 
 import chisel3.experimental.hierarchy.{instantiable, public}
-import chisel3.experimental.{BaseModule, ExtModule, Param}
+import chisel3.experimental.{BaseModule, ExtModule, Param, UnlocatableSourceInfo}
 
 /** A module or external module whose IO is generated from a specific generator.
   * This module may have no additional IO created other than what is specified
@@ -16,7 +16,7 @@ sealed trait FixedIOBaseModule[A <: Data] extends BaseModule {
   protected def ioGenerator: A
 
   @public
-  final val io = FlatIO(ioGenerator)
+  final val io = FlatIO(ioGenerator)(UnlocatableSourceInfo)
   endIOCreation()
 
 }