Deprecate DEF-less definitions (#1193)

test/asm/rs.asm

@@ -1,7 +1,7 @@
 
-a1 rb 1
-a2 rw 1
-a3 rl 1
+def a1 rb 1
+def a2 rw 1
+def a3 rl 1
 
 PRINTLN "a1 = ", a1
 PRINTLN "a2 = ", a2
@@ -9,9 +9,9 @@ PRINTLN "a3 = ", a3
 PRINTLN "_RS = ", _RS
 
 
-b1 rb 1
-b2 rw 1
-b3 rl 1
+def b1 rb 1
+def b2 rw 1
+def b3 rl 1
 
 PRINTLN "b1 = ", b1
 PRINTLN "b2 = ", b2
@@ -20,9 +20,9 @@ PRINTLN "_RS = ", _RS
 
 
 rsset 42
-c1 rb 1
-c2 rw 1
-c3 rl 1
+def c1 rb 1
+def c2 rw 1
+def c3 rl 1
 
 PRINTLN "c1 = ", c1
 PRINTLN "c2 = ", c2
@@ -31,13 +31,11 @@ PRINTLN "_RS = ", _RS
 
 
 rsreset
-d1 rb 1
-d2 rw 1
-d3 rl 1
+def d1 rb 1
+def d2 rw 1
+def d3 rl 1
 
 PRINTLN "d1 = ", d1
 PRINTLN "d2 = ", d2
 PRINTLN "d3 = ", d3
 PRINTLN "_RS = ", _RS
-
-