wr_si549: update field descriptions

modules/wr_si549_interface/si549_if_wb.cheby

@@ -34,8 +34,8 @@ memory-map:
           range: 8          
       - field:
           name: GAIN
-          comment: ADPLL_DELTA scaling factor 
-          description: RFREQ gain/scalefactor
+          comment: Unused
+          description: Unused
           range: 16-9          
       - field:
           name: CLK_DIV
@@ -51,15 +51,15 @@ memory-map:
             type: wire        
   - reg:
       name: GAIN
-      comment: DAC value gain (signed Q3.13)
-      description: DAC value gain (signed Q3.13)
+      comment: DAC value gain (signed Q8.8)
+      description: DAC value gain (signed Q8.8)
       width: 32
       access: rw
       children:
       - field:
           name: GAIN_VALUE
-          comment: DAC value gain (signed Q3.13)
-          description: DAC value gain (signed Q3.13)
+          comment: DAC value gain (signed Q8.8)
+          description: DAC value gain (signed Q8.8)
           range: 15-0
   - reg:
       name: GPSR