PDP11: Fix L2DR and L3DR comments

These instructions are referred to as L2Dr and L3Dr in the PDP-11/24
System Technical Manual (https://www.vt100.net/manx/details/1,23) and
their opcode strings call them L2DR and L3DR. These comments seem to be
a simple typo.

Author: thaliaarchi

PDP11/pdp11_cis.c

@@ -210,7 +210,7 @@ static int32 opntab[128][MAXOPN] = {
     {0, 0, 0, 0}, {0, 0, 0, 0},
     {0, 0, 0, 0}, {0, 0, 0, 0},
     {0, 0, 0, 0}, {0, 0, 0, 0},
-    {0, 0, 0, 0}, {0, 0, 0, 0},                         /* LD2R */
+    {0, 0, 0, 0}, {0, 0, 0, 0},                         /* L2DR */
     {0, 0, 0, 0}, {0, 0, 0, 0},
     {0, 0, 0, 0}, {0, 0, 0, 0},
     {0, 0, 0, 0}, {0, 0, 0, 0},
@@ -235,7 +235,7 @@ static int32 opntab[128][MAXOPN] = {
     {R0_DESC, R2_DESC, 0, 0},                           /* CVTNP */
     {R0_DESC, R2_DESC, R4_ARG, 0},                      /* ASHN */
     {R0_DESC, 0, 0, 0},                                 /* CVTLN */
-    {0, 0, 0, 0}, {0, 0, 0, 0},                         /* LD3R */
+    {0, 0, 0, 0}, {0, 0, 0, 0},                         /* L3DR */
     {0, 0, 0, 0}, {0, 0, 0, 0},
     {0, 0, 0, 0}, {0, 0, 0, 0},
     {0, 0, 0, 0}, {0, 0, 0, 0},