fixed demux bit 7 test and added note to primitives

test/unit_tests/demux_bit_7/test.prsim

@@ -22,7 +22,7 @@ cycle
 
 system "echo 'Output neutral checked'"
 
-set-qdi-channel-valid "my_demux.in" 8 255
+set-qdi-channel-valid "my_demux.in" 8 254
 cycle
 assert my_demux.in.v 1
 assert my_demux.in.a 0
@@ -59,12 +59,12 @@ set my_demux.out2.a 0
 set my_demux.out2.v 0
 cycle
 
-set-qdi-channel-valid "my_demux.in" 8 100
+set-qdi-channel-valid "my_demux.in" 8 101
 cycle
 assert my_demux.in.v 1
 assert my_demux.in.a 0
 
-assert-qdi-channel-valid "my_demux.out2" 7 100
+assert-qdi-channel-valid "my_demux.out2" 7 50
 set my_demux.out2.v 1
 cycle
 assert my_demux.in.a 1