Fix URL for firrtl spec (#7919)

Author: sequencer

include/circt/Dialect/FIRRTL/FIRRTLDialect.td

@@ -26,8 +26,8 @@ def FIRRTLDialect : Dialect {
   let summary = "Types and operations for firrtl dialect";
   let description = [{
     This dialect defines the `firrtl` dialect, which is used to lower from Chisel
-    code to Verilog.  For more information, see the [FIRRTL GitHub
-    page](https://github.com/freechipsproject/firrtl).
+    code to Verilog.  For more information, see the [FIRRTL Spec
+    page](https://github.com/chipsalliance/firrtl-spec).
   }];
 
   let hasConstantMaterializer = 1;